Apple’s careful to put the polish on its released products, but has a history of losing prototypes, too. (Justin Sullivan/GETTY IMAGES)

A North Carolina man has reportedly been asked to return a 3G MacBook prototype he purchased on Craigslist, CNET has found.

After buying the computer for spare parts for his repair business, Carl Frega was surprised to see a wholly unknown Apple-branded product hit his doorstep. The MacBook looked like a MacBook, but it also had an external antenna for 3G that could slide up and down the edge of the screen and a SIM card slot.

The laptop, CNET said, matches up with a 2008 Apple patent application, indicating that it is a real prototype.

Eventually, Frega tried to resell the oddity on eBay. That posting turned heads, and bids rose to over $70,000 before Apple asked for the auction to be shut down.

Shortly after that, Frega was contacted by the company to have someone pick up the device.

Apple is famously secretive about its products, but this isn’t the first time a prototype device has made it into the wild. Apart from the much-publicized iPhone 4 prototype obtained by Gizmodo in 2010, an eagle-eyed train rider in San Francisco also thinks he got a glimpse last month of the next iPhone.

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