Electric sports car maker Tesla announced a recall Wednesday for some of its Model S vehicles over possible weak welds on back seats. The recall applies to versions of the four-door sedan, which costs up to $87,000, produced between May 10, 2013 and June 8, 2013. Founder Elon Musk said on the company\'s blog that the strength of the weld on a mounting bracket in a back row seat \"could be weaker than intended.\" \"This reduces our confidence that the left hand seat back will be properly retained in the event of a crash,\" he wrote. Musk emphasized that no customers have complained about the problem and no injuries have been reported related to it. \"However, given the paramount importance of safety, we would like to reinforce the left striker bracket on cars produced during this period.\" \"This work has already been performed on cars that were in the factory, so the recall applies only to cars delivered in mid to late May and early June.\" Tesla said it will arrange to fix the problem at no cost to the owners. Tesla shares were up 1.3 percent to $104.68 in regular trade on the Nasdaq exchange Wednesday, but fell in after-hours deals to $104.20.