RISK FACTORS

You should consider carefully the following risks before you decide to purchase our common stock. Additional risks and uncertainties not presently known to us or that we currently believe are not important may also impair our business operations. If any of the following risks actually occur, our business, financial condition or results of operations could be materially adversely affected, the value of our common stock could decline and you may lose all or part of your investment.

Risks Relating to Our Business

Purchasers of aftermarket auto parts may not choose to shop online, which would prevent us from acquiring new customers who are necessary to the growth of our business

The online market for aftermarket auto parts is less developed than the online market for many other business and consumer products. Our success will depend in part on our ability to attract new customers and customers who have historically purchased auto parts through traditional retail and wholesale operations. Furthermore, we may have to incur significantly higher and more sustained advertising and promotional expenditures or price our products more competitively than we currently anticipate in order to attract additional online consumers to our websites and convert them into purchasing customers. Specific factors that could prevent prospective customers from purchasing from us include:

If the online market for auto parts does not gain widespread acceptance, our business and financial results may suffer.

We depend on search engines and other online sources to attract visitors to our websites, and if we are unable to attract these visitors and convert them into customers in a cost-effective manner, our business and results of operations will be harmed

Our success depends on our ability to attract online consumers to our websites and convert them into customers in a cost-effective manner. We use a variety of methods to attract visitors to our websites, but we are significantly dependent upon search engines, shopping comparison sites and other online sources for our website traffic. We are included in search results as a result of both paid search listings, where we purchase specific search terms that will result in the inclusion of our listing, and algorithmic searches that depend upon the searchable content on our sites. Algorithmic listings cannot be purchased and instead are determined and displayed solely by a set of formulas utilized by the search engine. We rely on both algorithmic and purchased listings to attract and direct consumers to our websites. Search engines, shopping comparison sites and other online sources revise their algorithms from time to time in an attempt to optimize their search results. If one or more of the search engines, shopping comparison sites or other online sources on which we rely for website traffic were to modify its general methodology for how it displays our websites, resulting in fewer consumers clicking through to our websites, our financial results could be adversely affected. If any free search engine or shopping comparison site on which we rely begins charging

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fees for listing or placement, or if one or more of the search engines, shopping comparison sites and other online sources on which we rely for purchased listings, modifies or terminates its relationship with us, our expenses could rise, we could lose customers and traffic to our websites could decrease. In addition, our success in attracting visitors who convert to customers will depend in part upon our ability to identify and purchase relevant search terms, provide relevant content on our sites, and effectively target our other marketing programs such as e-mail campaigns and affiliate programs. If we are unable to attract visitors to our websites and convert them to customers in a cost-effective manner, then our business and financial results may be harmed.

We are dependent upon relationships with suppliers in Taiwan, China and the United States for the vast majority of our products

We acquire substantially all of our products from manufacturers and distributors located in Taiwan, China and the United States. Our top five suppliers represented approximately 47.4% of our total product purchases in 2005 and 55.5% for the nine months ended September 30, 2006. Although we have long standing business relationships with many of our suppliers, we do not have any long-term contracts or exclusive agreements with our suppliers that would ensure our ability to acquire the types and quantities of products we desire at acceptable prices and in a timely manner. In addition, our ability to acquire products from our suppliers in amounts and on terms acceptable to us is dependent upon a number of factors that could affect our suppliers and which are beyond our control. For example, financial or operational difficulties that some of our suppliers may face may increase the cost of the products we purchase from them. In addition, the trend towards consolidation among auto parts suppliers may disrupt or end our relationship with some suppliers, and could lead to less competition and, consequently, higher prices.

In addition, because many of our suppliers are outside of the United States, additional factors could interrupt our relationships or affect our ability to acquire the necessary products on acceptable terms, including:

If we do not maintain our relationships with our existing suppliers or develop relationships with new suppliers on acceptable commercial terms, we may not be able to continue to offer a broad selection of merchandise at competitive prices and, as a result, we could lose customers and our sales could decline.

We recently acquired Partsbin and the integration of our businesses may be time consuming and expensive and may not be immediately successful, if at all

In May 2006, we completed the acquisition of Partsbin, an online retailer of aftermarket auto parts. As a result of the acquisition, we added 47 employees, and our available SKUs and net sales increased significantly. The acquisition of Partsbin has involved significant costs, has resulted in challenges integrating the diverse technologies used by each company and has placed, and may continue to place, pressures on our operational and financial infrastructure. We cannot assure you that our current cost structure or infrastructure will be adequate for the combined companies. To successfully integrate Partsbin, we anticipate that we will need to improve our operational and financial systems, procedures and controls and maintain our cost structure at appropriate levels.

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The Partsbin acquisition also expanded our product offerings, particularly in the area of engine parts and performance parts and accessories, and significantly increased our use of drop-ship as a method of fulfillment. We cannot assure you that we can effectively manage this new fulfillment model or address the market for these additional auto parts.

The integration of Partsbin may involve the consolidation of diverse business cultures, require substantial time and expenses, and distract management from other business matters. In addition, this acquisition may include significant intangible assets that are subject to periodic impairment testing which could result in substantial accounting charges. If we are unable to integrate Partsbin in an efficient and timely manner, our business and operating results will be harmed.

We face intense competition and operate in an industry with limited barriers to entry, and some of our competitors may have greater resources than us and may be better positioned to capitalize on the growing e-commerce auto parts market

The auto parts industry is competitive and highly fragmented, with products distributed through multi-tiered and overlapping channels. We compete with both online and offline retailers who offer OEM and aftermarket auto parts to either the DIY or DIFM customer segments. Current or potential competitors include the following:

Barriers to entry are low, and current and new competitors can launch websites at a relatively low cost. Many of our current and potential offline competitors have longer operating histories, larger customer bases, greater brand recognition and significantly greater financial, marketing, technical, management and other resources than we do. In addition, some of our competitors have used and may continue to use aggressive pricing tactics and devote substantially more financial resources to website and system development than we do. We expect that competition will further intensify in the future as Internet use and online commerce continue to grow worldwide. Increased competition may result in reduced operating margins, reduced profitability, loss of market share and diminished brand recognition.

We would also experience significant competitive pressure if any of our suppliers were to sell their products directly to customers. Since our suppliers have access to merchandise at very low costs, they could sell products at lower prices and maintain higher gross margins on their product sales than we can. In this event, our current and potential customers may decide to purchase directly from these suppliers. Increased competition from any supplier capable of maintaining high sales volumes and acquiring products at lower prices than us could significantly reduce our market share and adversely impact our financial results.

We rely on key personnel and may need additional personnel for the success and growth of our business

Our business is largely dependent on the personal efforts and abilities of key personnel including Mehran Nia, our Chief Executive Officer and President, and Michael McClane, our Chief Financial Officer, Executive Vice President of Finance, Treasurer and Secretary. Messrs. Nia and McClane, as well as any of our other key employees, can terminate their employment relationship with us at any time. We do not maintain key person life insurance on any officer or employee. Our performance also depends on our ability to identify, attract, retain and motivate highly skilled technical, managerial, merchandising, marketing and

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customer service personnel. Competition for such personnel is intense, and we cannot assure you that we will be successful in attracting and retaining such personnel. The loss of any key employee or our inability to attract or retain other qualified employees could harm our business and results of operations.

If our product catalog database is stolen or misappropriated or if a competitor is able to create a substantially similar catalog without infringing our rights, then we may lose an important competitive advantage

We have invested significant resources and time to build and maintain our product catalog, which is maintained in the form of an electronic database, and maps SKUs to relevant product applications based on vehicle makes, models and years. We believe that our product catalog provides us with an important competitive advantage in both driving traffic to our websites and converting that traffic to revenue by enabling customers to quickly locate the products they require. We cannot assure you that we can protect our product catalog from unauthorized copying or theft by a third party. In addition, it is possible that a competitor could develop a catalog or database that is similar to or more comprehensive than ours, without infringing our rights. In the event our product catalog is stolen, copied or otherwise replicated by a competitor, whether lawfully or not, we may lose an important competitive advantage and our business could be harmed.

We must continue to develop and maintain our brands, which is costly and may not generate corresponding revenue

Although we sell our products through a network of websites, our flagship websites are located at www.partstrain.com and www.autopartswarehouse.com , and our corporate website is located at www.usautoparts.com . Maintaining and strengthening these brands is an important factor in attracting new customers and building customer loyalty to generate repeat business. Accordingly, we intend to continue to implement promotional strategies to enhance our brand and attract new customers to our websites. These initiatives require significant expenditures and may not have a material positive impact on our brand identity or result in a commensurate increase in sales. In addition, building our brand will depend upon our ability to continue to provide a broad range of auto parts at competitive prices combined with high quality customer service. If we are unsuccessful in our branding efforts, the strength of our brands may decline and our sales could decline.

Our future operating results may fluctuate and may fail to meet market expectations, which could adversely affect the market price of our common stock

We expect that our revenue and operating results will continue to fluctuate from quarter to quarter due to various factors, many of which are beyond our control. If our quarterly revenue or operating results fall below the expectations of investors or securities analysts, the price of our common stock could significantly decline. The factors that could cause our operating results to fluctuate include, but are not limited to:

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Economic conditions may have an adverse effect on the demand for aftermarket auto parts and could adversely affect our sales and operating results

We sell aftermarket auto parts consisting of body and engine parts used for repair and maintenance, performance parts used to enhance performance or improve aesthetics, and accessories that increase functionality or enhance a vehicle’s features. Demand for our products may be adversely affected by general economic conditions. In declining economies, consumers often defer regular vehicle maintenance and may forego purchases of nonessential performance products, which can result in a decrease in demand for auto parts in general. In expanding economies, consumers may be more likely to purchase new vehicles instead of repairing existing vehicles or they may be less price sensitive, leading to an increase in OEM parts sales at dealerships, either of which could also result in a decline in our sales. If such decreases in demand for our products are not offset by other factors, such as the deferral of new car purchases in declining economies, which may result in more required repairs for older vehicles, or the purchase of performance parts and accessories in expanding economies, our financial condition and results of operations would suffer.

If we are unable to manage the challenges associated with our international operations, the growth of our business could be limited and our business could suffer

We maintain business operations in the United States and the Philippines and outsourced call centers in both India and the Philippines. These international operations include development and maintenance of our websites, software development, enhancements of our online marketing technologies, and customer support services. We also operate a Canadian subsidiary to facilitate sales in Canada. We are subject to a number of risks and challenges that specifically relate to our international operations. Our international operations may not be successful if we are unable to meet and overcome these challenges, which could limit the growth of our business and may have an adverse effect on our business and operating results. These risks and challenges include:

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If our fulfillment operations are interrupted for any significant period of time or are not sufficient to accommodate increased demand, our sales would decline and our reputation could be harmed

Our success depends on our ability to successfully receive and fulfill orders and to promptly deliver our products to our customers. Although we recently added a complementary drop-ship fulfillment method, largely for our Partsbin products, the majority of orders for our other products are filled from our inventory through our distribution centers, where all our inventory management, packaging, labeling and product return processes are performed. Increased demand and other considerations may require us to expand our distribution centers or transfer our fulfillment operations to larger facilities in the future.

Our distribution centers are susceptible to damage or interruption from human error, fire, flood, power loss, telecommunications failures, terrorist attacks, acts of war, break-ins, earthquakes and similar events. We do not currently maintain back-up power systems at our fulfillment centers. We do not presently have a formal disaster recovery plan and our business interruption insurance may be insufficient to compensate us for losses that may occur in the event operations at our fulfillment center are interrupted. Any interruptions in our fulfillment operations for any significant period of time, including interruptions resulting from the expansion of our existing facilities or the transfer of operations to a new facility, could damage our reputation and brand and substantially harm our business and results of operations. In addition, if we do not successfully expand our fulfillment capabilities in response to increases in demand, we may not be able to substantially increase our net sales.

We are dependent upon third parties for distribution and fulfillment operations with respect to many of our products

For a number of the products that we sell, we outsource the distribution and fulfillment operation and are dependent on our distributors to manage inventory, process orders and distribute those products to our customers in a timely manner. For the nine months ended September 30, 2006, we fulfilled 11.4% of our net sales through a single supplier. Our agreements with this supplier may be terminated at any time by either party, with 120 to 365 days’ notice. In addition, we do not have definitive agreements with many of our primary international suppliers. If we do not maintain our existing relationships with our distributors on acceptable commercial terms, we will need to obtain other suppliers and may not be able to continue to offer a broad selection of merchandise at competitive prices, and our sales may decrease.

In addition, because we outsource to distributors a number of these traditional retail functions relating to those products, we have limited control over how and when orders are fulfilled. We also have limited control over the products that our distributors purchase or keep in stock, and our agreements with most of our distributors do not require them to set aside any amount of inventory to fulfill our orders or to give our orders priority over other resellers to whom they sell. Our distributors may not accurately forecast the products that will be in high demand or they may allocate popular products to other resellers, resulting in the unavailability of certain products for sale on our websites. Any inability to offer a broad array of products at competitive prices and any failure to deliver those products to our customers in a timely and accurate manner may damage our reputation and brand and could cause us to lose customers.

Our ability to sustain or increase our profitability will suffer if we fail to manage our growth effectively

In recent years we have experienced rapid growth that has placed, and will continue to place, pressures on our operational and financial infrastructure. Our workforce has increased from 114 employees as of December 31, 2003 to 434 employees as of September 30, 2006. Our net sales have increased from $31.7 million in 2003 to $83.7 million for the nine months ended September 30, 2006. Our strategy for growth includes efforts to increase our operating efficiencies. Our recent expansion and planned growth have

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placed, and are expected to continue to place, a strain on our infrastructure, operations and managerial resources. We intend to further increase the size of our operations, and we expect our operating expenses to increase, as we, among other things:

Our success depends upon our ability to manage our operations and our growth effectively. To be successful, we will need to improve our operational and financial systems, procedures and controls, maintain our cost structure at appropriate levels, manage international operations, and hire additional personnel. We cannot assure you that our efforts will be successful or that we can improve our systems, procedures and controls in a timely manner. Delays or problems associated with any improvements or expansion of our systems, procedures and controls could harm our business and operating results. In addition, we may fail to accurately estimate and assess our increased operating expenses as we grow. As our operating expenses increase, we will need to grow our revenue in order to maintain and increase our profitability.

Challenges by OEMs to the validity of aftermarket auto parts and claims of infringement could adversely affect our business

Original equipment manufacturers have attempted to use claims of intellectual property infringement against manufacturers and distributors of aftermarket auto parts to restrict or eliminate the sale of aftermarket auto parts that are the subject of the claims. We have received in the past, and we anticipate we may in the future, receive communications alleging that certain products we sell infringe third-party patents, copyrights, trademarks and trade names or other intellectual property rights. For example, in December 2005, Ford Global Technologies, LLC filed a complaint with the United States International Trade Commission, or USITC, against us and five other named respondents, including four Taiwan-based manufacturers. Ford currently alleges in this action that we and the other respondents infringed ten design patents that Ford claims cover eight parts for the 2004-2005 Ford F-150 truck (see “Business — Legal Proceedings”). Ford has asked the USITC to issue a permanent general exclusion order excluding from entry into the United States all auto parts that infringe the ten Ford design patents and that are imported into the United States, sold for importation in the United States, or sold within the United States after importation. Ford also seeks a permanent order directing us and the other respondents to cease and desist from, among other things, selling, marketing, advertising, distributing and offering for sale imported auto parts that infringe the design patents. To date, our sales of these parts have been minimal, but as the design for the 2004 model is incorporated into later year models of the F-150 and these trucks have been on the road longer, sales of aftermarket replacement parts for these trucks may increase substantially. Furthermore, if Ford continues to pursue, expands or escalates its claims against us, or if other OEMs commence similar actions, and any of them are successful in these actions, we could be restricted or prohibited from selling certain aftermarket products and the aftermarket auto parts industry could decline significantly, which could have a material adverse effect on our business, financial condition and results of operations.

Future infringement claims could also result in increased costs of doing business arising from increased legal expenses, adverse judgments or settlements or changes to our business practices required to

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settle such claims or satisfy any judgments. Litigation could result in interpretations of the law that require us to change our business practices or otherwise increase our costs and harm our business. We do not maintain insurance coverage to cover the types of claims that could be asserted. If a successful claim were brought against us, it could expose us to significant liability.

If we fail to offer a broad selection of products and brands at competitive prices to meet our customers’ demands, our revenue could decline

In order to expand our business, we must successfully offer, on a continuous basis, a broad selection of auto parts that meet the needs of our customers. Our auto parts are used by consumers for a variety of purposes, including repair, performance, improved aesthetics and functionality. In addition, to be successful, our product offerings must be broad and deep in scope, competitively priced, well-made, innovative and attractive to a wide range of consumers. We cannot predict with certainty that we will be successful in offering products that meet all of these requirements. If our product offerings fail to satisfy our customers’ requirements or respond to changes in customer preferences, our revenue could decline.

Future acquisitions could disrupt our business and harm our financial condition

Key components of our growth strategy include expanding our product offerings, increasing our customer base and improving the customer experience. In pursuit of our growth strategy, we expect that we will selectively pursue acquisitions of businesses, technologies or services in order to expand our capabilities, enter new markets or increase our market share. We have limited experience in making acquisitions, and we compete with larger, better financed companies in identifying and completing acquisitions. We cannot assure you that we will be able to identify or consummate any future acquisitions on favorable terms, or at all. Integrating any newly acquired businesses, technologies or services is likely to be expensive and time consuming. To finance any acquisitions, it may be necessary for us to raise additional capital through public or private financings. Additional funds may not be available on terms that are favorable to us, and, in the case of equity financings, would result in dilution to our stockholders. If we do complete any acquisitions, we may be unable to operate the acquired businesses profitably, realize the anticipated synergies from the acquisition or otherwise implement our strategy successfully. If we are unable to integrate any newly acquired entities, technologies or services effectively or retain the key employees of any acquired companies, our business and results of operations will suffer. The time and expense associated with finding suitable and compatible businesses, technologies or services could also disrupt our ongoing business and divert our management’s attention. Future acquisitions by us could also result in large and immediate write-offs, assumption of debt and unforeseen liabilities and significant adverse accounting charges, any of which could substantially harm our business, financial condition and results of operations. We have no current plans, agreements or commitments with respect to any acquisitions.

We may be subject to liability for sales and other taxes and penalties, which could have an adverse effect on our business

We currently collect sales or other similar taxes only on the shipment of goods to the states of California, New Jersey and Tennessee. The U.S. Supreme Court has ruled that vendors whose only connection with customers in a state is by common carrier or the U.S. mail are free from state-imposed duties to collect sales and use taxes in that state. However, states could seek to impose additional income tax obligations or sales tax collection obligations on out-of-state companies such as ours, which engage in or facilitate online commerce, based on their interpretation of existing laws, including the Supreme Court ruling, or specific facts relating to us. If sales tax obligations are successfully imposed upon us by a state or other jurisdiction, we could be exposed to substantial tax liabilities for past sales and penalties and fines for

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failure to collect sales taxes. We could also suffer decreased sales in that state or jurisdiction as the effective cost of purchasing goods from us increases for those residing in that state or jurisdiction.

In addition, a number of states, as well as the U.S. Congress, have been considering various initiatives that could limit or supersede the Supreme Court’s apparent position regarding sales and use taxes on Internet sales. If any of these initiatives are enacted, we could be required to collect sales and use taxes in additional states and our revenue could be adversely affected. Furthermore, the U.S. Congress has not yet extended a moratorium, which was first imposed in 1998 but has since expired, on state and local governments’ ability to impose new taxes on Internet access and Internet transactions. The imposition by state and local governments of various taxes upon Internet commerce could create administrative burdens for us as well as substantially impair the growth of e-commerce and adversely affect our revenue and profitability. Since our service is available over the Internet in multiple states, these jurisdictions may require us to qualify to do business in these states. If we fail to qualify in a jurisdiction that requires us to do so, we could face liabilities for taxes and penalties.

If we are unable to provide satisfactory customer support, our reputation would be harmed and we could lose customers

We believe that our experienced customer support personnel provide us with a key competitive advantage by providing a positive shopping experience for our customers. We maintain customer support centers in California and have outsourced call centers in the Philippines and India. Any material disruption or slowdown in our customer support services resulting from telephone or Internet failures, power or service outages, natural disasters, labor disputes, or other events could make it difficult or impossible to provide adequate customer support. Furthermore, we may be unable to attract and retain an adequate number of competent customer support representatives, which is essential in creating a favorable customer experience. In addition, because our outsourced call centers are located in the Philippines and India, we may experience difficulties in training our support team or monitoring the level of support provided. If we are unable to continually provide adequate and trained staffing for our customer support operations, our reputation could be seriously harmed and our sales could decline. Further, we cannot assure you that call volumes will not exceed our present system capacities. If this occurs, we could experience delays in accepting orders, responding to customer inquiries and addressing customer concerns. Because our success depends in large part on keeping our customers satisfied, any failure to provide satisfactory levels of customer support would likely impair our reputation and we could lose customers.

We could be liable for breaches of security on our websites

A fundamental requirement for e-commerce is the secure transmission of confidential information over public networks. Anyone who is able to circumvent our security measures could misappropriate proprietary information or cause interruptions in our operations. Although we have developed systems and processes that are designed to protect consumer information and prevent fraudulent credit card transactions and other security breaches, failure to mitigate such fraud or breaches may adversely affect our operating results. We may be required to expend significant capital and other resources to protect against potential security breaches or to alleviate problems caused by any breach. We rely on licensed encryption and authentication technology to provide the security and authentication necessary for secure transmission of confidential information, including credit card numbers. Advances in computer capabilities, new discoveries in the field of cryptography, or other events or developments may result in a compromise or breach of the algorithms that we use to protect customer transaction data. In the event someone circumvents our security measures, it could seriously harm our business and reputation and we could lose customers. Security breaches could also expose us to a risk of loss or litigation and possible liability for failing to secure confidential customer information.

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The success of our business depends on the continued growth of the Internet as a retail marketplace and the related expansion of the Internet infrastructure

Our future success depends upon the continued and widespread acceptance and adoption of the Internet as a vehicle to purchase products. If customers or manufacturers are unwilling to use the Internet to conduct business and exchange information, our business will fail. The commercial acceptance and use of the Internet may not continue to develop at historical rates, or may not develop as quickly as we expect. The growth of the Internet, and in turn the growth of our business, may be inhibited by concerns over privacy and security, including concerns regarding “viruses” and “worms,” reliability issues arising from outages or damage to Internet infrastructure, delays in development or adoption of new standards and protocols to handle the demands of increased Internet activity, decreased accessibility, increased government regulation, and taxation of Internet activity. In addition, our business growth may be adversely affected if the Internet infrastructure does not keep pace with the growing Internet activity and is unable to support the demands placed upon it, or if there is any delay in the development of enabling technologies and performance improvements.

If we do not respond to technological change, our websites could become obsolete and our financial results and conditions could be adversely affected

We maintain a network of websites which requires substantial development and maintenance efforts and entails significant technical and business risks. To remain competitive, we must continue to enhance and improve the responsiveness, functionality and features of our websites. The Internet and the e-commerce industry are characterized by rapid technological change, the emergence of new industry standards and practices and changes in customer requirements and preferences. Therefore, we may be required to license emerging technologies, enhance our existing websites, develop new services and technology that address the increasingly sophisticated and varied needs of our current and prospective customers, and adapt to technological advances and emerging industry and regulatory standards and practices in a cost-effective and timely manner. Our ability to remain technologically competitive may require substantial expenditures and lead time and our failure to do so may harm our business and results of operations.

System failures, including failures due to natural disasters or other catastrophic events, could prevent access to our websites, which could reduce our net sales and harm our reputation

Our sales would decline and we could lose existing or potential customers if they are not able to access our websites or if our websites, transaction processing systems or network infrastructure does not perform to our customers’ satisfaction. Any Internet network interruptions or problems with our websites could:

We have experienced brief computer system interruptions in the past, and we believe they will continue to occur from time to time in the future. Our systems and operations are also vulnerable to damage or interruption from a number of sources, including a natural disaster or other catastrophic event such as an earthquake, typhoon, volcanic eruption, fire, flood, terrorist attack, power loss, telecommunications failure, physical and electronic break-ins and other similar events. For example, our headquarters and the majority of our infrastructure, including some of our servers, are located in Southern California, a seismically active

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region. We also maintain offshore and outsourced operations in the Philippines, an area that was recently subjected to a typhoon and a volcanic eruption. In addition, California has in the past experienced power outages as a result of limited electrical power supplies. Such outages, natural disasters and similar events may recur in the future and could disrupt the operation of our business. Our technology infrastructure is also vulnerable to computer viruses, physical or electronic break-ins and similar disruptions. Although the critical portions of our systems are redundant and back up copies are maintained offsite, not all of our systems and data are fully redundant. We do not presently have a formal disaster recovery plan in effect and may not have sufficient insurance for losses that may occur from natural disasters or catastrophic events. Any substantial disruption of our technology infrastructure could cause interruptions or delays in our business and loss of data or render us unable to accept and fulfill customer orders or operate our websites in a timely manner, or at all.

Capacity constraints on our technology infrastructure would harm our business, prospects, results of operations and financial condition

If the volume of traffic on our websites or the number of purchases made by customers increases substantially, we may need to further expand and upgrade our technology, transaction processing systems and network infrastructure. Capacity constraints can cause unanticipated system disruptions, slower response times, degradation in levels of customer service, impaired quality and delays in reporting accurate financial information.

We may be unable to project accurately the rate or timing of traffic increases or successfully and cost-effectively upgrade our systems and infrastructure in time to accommodate future traffic levels on our websites. Any such upgrades to our systems and infrastructure will require substantial expenditures. In addition, we may be unable to upgrade and expand our transaction processing systems in an effective and timely manner or to integrate any newly developed or purchased functionality with our existing systems. Any inability to efficiently upgrade our systems and infrastructure in a timely manner to account for such growth and integrations may cause unanticipated system disruptions, slower response times, degradation in levels of customer service, impaired quality, delayed order fulfillment, any of which could result in a decline in our sales and harm our reputation.

We depend on third-party delivery services to deliver our products to our customers on a timely and consistent basis, and any deterioration in our relationship with any one of these third parties or increases in the fees that they charge could adversely affect our business and financial condition

We rely on third parties for the shipment of our products, but because we do not have written long-term agreements with any of these third parties, we cannot be sure that these relationships will continue on terms favorable to us, or at all. Increases in shipping costs could harm our business, prospects, financial condition and results of operations by increasing our costs of doing business and resulting in reduced gross margins. In addition, if our relationships with these third parties are terminated or impaired, or if these third parties are unable to deliver products for us, whether through labor shortage, slow down or stoppage, deteriorating financial or business condition, responses to terrorist attacks or for any other reason, we would be required to use alternative carriers for the shipment of products to our customers. Changing carriers could have a negative effect on our business and operating results due to reduced visibility of order status and package tracking and delays in order processing and product delivery, and we may be unable to engage alternative carriers on a timely basis, upon terms favorable to us, or at all.

We face exposure to product liability lawsuits

The automotive industry in general has been subject to a large number of product liability claims due to the nature of personal injuries that result from car accidents or malfunctions. As a distributor of auto

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parts, we could be held liable for the injury or damage caused if the products we sell are defective or malfunction. While we carry insurance against product liability claims, if the damages in any given action were high or we were subject to multiple lawsuits, the damages and costs could exceed the limits of our insurance coverage. If we were required to pay substantial damages as a result of these lawsuits, it may seriously harm our business and financial condition. Even defending against unsuccessful claims could cause us to incur significant expenses and result in a diversion of management’s attention. In addition, even if the money damages themselves did not cause substantial harm to our business, the damage to our reputation and the brands offered on our websites could adversely affect our future reputation, brand and could result in a decline in our net sales and profitability.

Existing or future government regulation could expose us to liabilities and costly changes in our business operations and could reduce customer demand for our products and services

We are subject to federal and state consumer protection laws and regulations, including laws protecting the privacy of customer non-public information and regulations prohibiting unfair and deceptive trade practices, as well as laws and regulations governing businesses in general and the Internet and e-commerce. Additional laws and regulations may be adopted with respect to the Internet, the effect of which on e-commerce is uncertain. These laws may cover issues such as user privacy, spyware and the tracking of consumer activities, marketing e-mails and communications, other advertising and promotional practices, money transfers, pricing, content and quality of products and services, taxation, electronic contracts and other communications, intellectual property rights, and information security. Furthermore, it is not clear how existing laws such as those governing issues such as property ownership, sales and other taxes, trespass, data mining and collection, and personal privacy apply to the Internet and e-commerce. To the extent we expand into international markets, we will be faced with complying with local laws and regulations, some of which may be materially different than U.S. laws and regulations. Any such foreign law or regulation, any new U.S. law or regulation, or the interpretation or application of existing laws and regulations to the Internet or other online services, may have a material adverse effect on our business, prospects, financial condition and results of operations by, among other things, impeding the growth of the Internet, subjecting us to fines, penalties, damages or other liabilities, requiring costly changes in our business operations and practices, and reducing customer demand for our products and services. We do not maintain insurance coverage to cover the types of claims or liabilities that could arise as a result of such regulation.

If we are unable to protect our intellectual property rights, our reputation and brand could be impaired and we could lose customers

We regard our trademarks, trade secrets and similar intellectual property as important to our success. We rely on trademark and copyright law, and trade secret protection, and confidentiality and/or license agreements with employees, customers, partners and others to protect our proprietary rights. We cannot be certain that we have taken adequate steps to protect our proprietary rights, especially in countries where the laws may not protect our rights as fully as in the United States. In addition, third parties may infringe or misappropriate our proprietary rights, and we could be required to incur significant expenses to preserve them. We have federally-registered and common law trademarks, as well as pending federal trademark registrations for several marks. Even if we obtain approval of such pending registrations, the resulting registrations may not adequately cover our inventions or protect us against infringement by others. Effective trademark, service mark, copyright, patent and trade secret protection may not be available in every country in which our products and services may be made available online. We also currently own or control a number of Internet domain names, including www.usautoparts.com , www.partstrain.com and www.autopartswarehouse.com . We may be unable to protect these domain names or acquire or maintain

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relevant domain names in the United States and in other countries. If we are not able to protect our trademarks, domain names or other intellectual property, we may experience difficulties in achieving and maintaining brand recognition and customer loyalty.

Our e-commerce system is dependent on open-source software, which exposes us to uncertainty and potential liability

We utilize open-source software such as Linux, Apache, MySQL, PHP, Fedora and Perl throughout our web properties and supporting infrastructure. Open-source software is maintained and upgraded by a general community of software developers under various open-source licenses, including the GNU General Public License, or GPL. These developers are under no obligation to maintain, enhance or provide any fixes or updates to this software in the future. Additionally, under the terms of the GPL and other open-source licenses, we may be forced to release to the public source-code internally developed by us pursuant to such licenses. Furthermore, if any of these developers contribute any code of others to any of the software that we use, we may be exposed to claims and liability for intellectual property infringement. A number of lawsuits are currently pending against third parties over the ownership rights to the various components within some open-source software that we use. If the outcome of these lawsuits is unfavorable, we may be held liable for intellectual property infringement based on our use of these open-source software components. We may also be forced to implement changes to the code-base for this software or replace this software with internally developed or commercially licensed software.

We rely on bandwidth and data center providers and other third parties to provide products to our customers, and any failure or interruption in the services provided by these third parties could disrupt our business and cause us to lose customers

We rely on third-party vendors, including data center and bandwidth providers. Any disruption in the network access or co-location services, which are the services that house and provide Internet access to our servers, provided by these third-party providers or any failure of these third-party providers to handle current or higher volumes of use could significantly harm our business. Any financial or other difficulties our providers face may have negative effects on our business, the nature and extent of which we cannot predict. We exercise little control over these third-party vendors, which increases our vulnerability to problems with the services they provide. We also license technology and related databases from third parties to facilitate elements of our e-commerce platform. We have experienced and expect to continue to experience interruptions and delays in service and availability for these elements. Any errors, failures, interruptions or delays experienced in connection with these third-party technologies could negatively impact our relationship with our customers and adversely affect our business.

Our systems also heavily depend on the availability of electricity, which also comes from third-party providers. If we were to experience a major power outage, we would have to rely on back-up generators. These back-up generators may not operate properly through a major power outage, and their fuel supply could also be inadequate during a major power outage. Information systems such as ours may be disrupted by even brief power outages, or by the fluctuations in power resulting from switches to and from backup generators. This could disrupt our business and cause us to lose customers.

The United States government may substantially increase border controls and impose restrictions on cross-border commerce that may substantially harm our business

We purchase a substantial portion of our products, including our Kool-Vue mirrors, from suppliers in Taiwan and China. Restrictions on shipping goods into the United States from other countries pose a substantial risk to our business. Particularly since the terrorist attacks on September 11, 2001, the United

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States government has substantially increased border surveillance and controls. If the United States were to impose further border controls and restrictions, impose quotas, tariffs or import duties, increase the documentation requirements applicable to cross border shipments or take other actions that have the effect of restricting the flow of goods from Taiwan or China to the United States, we may have greater difficulty acquiring our inventory in a timely manner, experience shipping delays, or incur increased costs and expenses, all of which would substantially harm our business and results of operations.

Risks Relating to this Offering and Ownership of Our Common Stock

No public market for our common stock currently exists and an active trading market may not develop or be sustained following this offering

No public market for our common stock currently exists, and we cannot be certain that an active trading market for our common stock will develop or be sustained following this offering. Further, we cannot be certain that the market price of our common stock will not decline below the initial public offering price. The initial public offering price was determined by negotiation among us and the underwriters based upon several factors and may not be indicative of future market prices for our common stock.

Our stock price may be volatile, which may result in losses to our stockholders

The market prices of technology and e-commerce companies generally have been extremely volatile and have recently experienced sharp share price and trading volume changes. The trading price of our common stock is likely to be volatile and could fluctuate widely in response to, among other things, the risk factors described in this prospectus and other factors beyond our control such as fluctuations in the operations or valuations of companies perceived by investors to be comparable to us and conditions or trends in the Internet or auto parts industries.

The stock markets have historically experienced significant price and trading volume fluctuations. These fluctuations, as well as general economic and political conditions unrelated to our performance, may adversely affect the price of our common stock. In particular, following initial public offerings, the market prices for stocks of Internet and technology-related companies often reach levels that bear no established relationship to the operating performance of these companies. These market prices are generally not sustainable and could vary widely. In the past, following periods of volatility in the market price of a public company’s securities, securities class action litigation has often been initiated. Securities litigation against us could result in substantial costs and divert our management’s attention from other business concerns, which could seriously harm our business.

We have broad discretion as to the use of proceeds from this offering and may not use the proceeds effectively

We estimate the net proceeds of this offering to be approximately $            million. Our management will retain broad discretion as to the allocation of the proceeds and may spend these proceeds in ways in which our stockholders may not agree. The failure of our management to apply these funds effectively could result in unfavorable returns and uncertainty about our prospects, each of which could cause the price of our common stock to decline.

Our principal stockholders, executive officers and directors own a significant percentage of our stock and will continue to have significant control of our management and affairs after this offering

Upon completion of this offering, our executive officers and directors and entities that are affiliated with them will beneficially own approximately         % of our outstanding shares of common stock. This

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significant concentration of share ownership may adversely affect the trading price for our common stock because investors often perceive disadvantages in owning stock in companies with controlling stockholders. Also, these stockholders, acting together, will be able to control our management and affairs and matters requiring stockholder approval including the election of our entire board of directors and certain significant corporate actions such as mergers, consolidations or the sale of substantially all of our assets. As a result, this concentration of ownership could delay, defer or prevent others from initiating a potential merger, takeover or other change in our control, even if these actions would benefit our other stockholders and us.

A large number of additional shares may be sold into the public market in the near future, which may cause the market price of our common stock to decline significantly, even if our business is doing well

Sales of a substantial amount of common stock in the public market, or the perception that these sales may occur, could adversely affect the market price of our common stock. After this offering, we will have outstanding             shares of common stock. This includes the             shares we are selling in this offering, which may be resold in the public market immediately. All of the remaining 36,388,226 shares outstanding after the offering will become available for resale in the public market 180 days after the date of this prospectus (subject to extension in certain circumstances) due to agreements these stockholders have with us or the underwriters. However, the underwriters can waive this restriction and allow these stockholders to sell their shares at any time. As restrictions on resale end, the market price could drop significantly if the holders of these restricted shares sell them or are perceived by the market as intending to sell them. For a more detailed description, see “Shares Eligible for Future Sale.”

New stockholders will incur substantial and immediate dilution as a result of this offering

The initial public offering price is substantially higher than the book value per share of our outstanding common stock. As a result, investors purchasing common stock in this offering will incur substantial and immediate dilution. At the initial public offering price of $            per share, purchasers in this public offering will experience immediate and substantial dilution of approximately $            per share, representing the difference between our historical net tangible book value per share after giving effect to this offering and the initial public offering price. In addition, purchasers of common stock in this offering will have contributed approximately             % of the aggregate price paid by all purchasers of our stock but will own only approximately             % of our common stock outstanding after this offering. In addition, we have issued options to acquire common stock at prices significantly below the public offering price. To the extent such options are ultimately exercised, there will be further dilution to investors in this offering.

If we fail to maintain an effective system of internal control over financial reporting or are not able to adequately address certain identified significant deficiencies in our system of internal controls or comply with Section 404 of the Sarbanes-Oxley Act of 2002, we may not be able to accurately report our financial results or prevent fraud, and our stock price could decline

Our auditors have identified certain significant deficiencies in our system of internal control over financial reporting that are primarily related to our need to hire additional financial and accounting employees, as well as our need to upgrade our accounting systems and improve the documentation of our key assumptions, estimates, accounting policies and procedures. If we fail to adequately address these significant deficiencies and are not able to staff our accounting and finance department with the appropriate complement of experienced employees, we may not be able to improve our system of internal control over financial reporting to comply with the reporting requirements applicable to a public companies in the United States. Furthermore, it is possible that our auditors will identify material weaknesses or additional significant deficiencies in the future in our system of internal control over financial reporting. Our failure to

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address any deficiencies or weaknesses in our internal control over financial reporting or to properly maintain an effective system of internal control over financial reporting could impact our ability to prevent fraud or to issue our financial statements in a timely manner that present fairly our financial condition and results of operations. The existence of any such deficiencies or weaknesses, even if cured, may also lead to the loss of investor confidence in the reliability of our financial statements, could harm our business and negatively impact the trading price of our common stock. Such deficiencies or material weaknesses may also subject us to lawsuits, investigations and other penalties.

In addition, Section 404 of the Sarbanes-Oxley Act of 2002 will require us to evaluate and report on our internal control over financial reporting and have our independent auditors attest to our evaluation, beginning with our Annual Report on Form 10-K for the year ending December 31, 2008. We have prepared an internal plan of action for compliance with Section 404 and for strengthening and testing our system of internal control to provide the basis for our report, but we cannot assure you that this plan of action will be sufficient to meet the rigorous requirements of Section 404, and our independent auditors may issue an adverse opinion regarding management’s assessment of Section 404 compliance. It is also possible that our independent auditors may not be in a position to adequately assess our compliance with Section 404 on a timely basis, which could lead to our inability to comply with our reporting requirements under the Exchange Act of 1934, as amended (the “Exchange Act”). Our failure to comply with Section 404 or our reporting requirements would reduce investors’ confidence in our financial statements and harm our stock price and could subject us to a variety of administrative sanctions, including the suspension or delisting of our common stock from the NASDAQ Global Market and the inability of registered broker/dealers to make a market in our common stock, which could also reduce our stock price.

We will incur increased costs and compliance risks as a result of being a public company

As a public company, we expect to incur significant legal, accounting and other expenses that we did not incur as a private company. These expenses are associated with our public company reporting requirements and certain corporate governance requirements, including requirements under the Sarbanes-Oxley Act of 2002 and the new rules implemented by the SEC and the NASDAQ Stock Market. We expect that compliance with these rules and regulations, in particular Section 404 of the Sarbanes-Oxley Act of 2002, will substantially increase our legal and financial compliance costs and will likely require us to hire additional personnel and/or consultants. Like many smaller public companies, we expect to face a significant impact from required compliance with Section 404 of the Sarbanes-Oxley Act of 2002. The process of strengthening our internal control and complying with Section 404 will be expensive and time consuming, and will require significant time and attention from our management team. We are currently evaluating and monitoring developments with respect to these new rules, and we cannot predict or estimate the amount of additional costs we may incur or the timing of such costs.

We also expect these new rules and regulations may make it more difficult and more expensive for us to obtain director and officer liability insurance and we may be required to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. As a result, it may be more difficult for us to attract and retain qualified individuals to serve on our board of directors or as executive officers.

We do not intend to pay dividends on our common stock

We currently intend to retain any future earnings and do not expect to pay any cash dividends on our capital stock for the foreseeable future.

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Our charter documents could deter a takeover effort, which could inhibit your ability to receive an acquisition premium for your shares

Provisions of our certificate of incorporation, bylaws and Delaware law could make it more difficult for a third party to acquire us, even if doing so would be beneficial to our stockholders. For a more detailed discussion of these provisions, see “Description of Capital Stock — Anti-Takeover Provisions.”

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