Online auto parts and accessories retailer U.S. Auto Parts Network Inc. reported strong sales for the fourth quarter of 2010 and the full year.

For the full year ended Jan. 1, U.S. Auto Parts, No. 91 in the Internet Retailer Top 500 reported:

• Total sales of $262.3 million, an increase of 48.8% from $176.3 million last year. The total includes about $39.1 million in revenue from its acquisition of J.C. Whitney, the company says.
• Net loss was $13.9 million, including $3.1 million in restructuring charges related to the Whitney acquisition, compared with net income of $1.3 million in 2009.
• Marketing expense, excluding advertising expense, was $38.7 million or 14.8% of sales.
• Fulfillment expense was $14.9 million or 5.7% of sales.
• Technology expense was $5.9 million or 2.2% of sales.

U.S. Auto Parts acquired Whitney Automotive Group in August 2010 in a deal valued at $27.5 million and the assumption of approximately $11 million in trade-related and other payables.

“We continue to be on track with the integration of our recent acquisition, Whitney Automotive Group,” says CEO Shane Evangelist. “We have successfully converted the catalog, cut over StylinTruck and CarParts to our platform and are on track to cut over J.C. Whitney by the end of Q2 2011.”

For the fourth quarter, U.S. Auto Parts reported:

• Total sales of $80.5 million, a 75.7% increase from $45.8 million in Q4 2009. The total includes about $25.5 million is Whitney-related revenue, the retailer says.
• Net loss was about $2.9 million compared with net income of $586,000.
• Marketing expense, excluding advertising expense, was $6.1 million or 7.6% of sales.
• Fulfillment expense was $4.7 million or 5.8% of sales.
• Technology expense was $2.1 million or 2.6% of sales in the fourth quarter of 2010.
• Conversion rate was 1.73% compared with 1.47% in the prior year quarter.
• Average ticket was $122 versus $116.
• Unique web site visitors were 37.4 million compared with 25.1 million.