Mehran Nia, the co-founder and former chief executive of Carson online parts retailer U.S. Auto Parts Network Inc., is calling on the company to explore a sale.

In a letter to the company’s board of directors Tuesday, Nia said that although the company has had “double-digit year-over-year revenue growth, and independent third-party projections indicating the industry will double within five years,” the company would “remain significantly undervalued as a stand-alone publicly-traded enterprise.”

As a result, Nia, who is also a board member and owns a nearly 12-percent stake in the company, said the board should hire an investment bank to look into “strategic alternatives to maximize shareholder value,” including selling the company.

In the letter, Nia said he has discussed the matter with potential buyers and is convinced there are a number that would be interested in purchasing U.S. Auto Parts “at a significant premium to its recent trading valuation.”

He said he believes the company, shares of which trade for less than $2, should be valued at between $4 and $6 but that the company will keep trading below that value because it is too small to attract big, institutional shareholders.

U.S. Auto Parts executives did not return requests for comment. The company’s shares rose 17 percent Tuesday to close at $1.93.