The person selling it says they were "accidentally sent one upon renewing my contract".
Apple doesn't sell these models, it uses them to test software and iron out bugs. As such, it probably won't work as a phone. But that hasn't stopped Apple fans from piling in to get their hands on an ultra rare piece of technology.
"As you can see from the photos, iOS 8 has not been placed on this device, rather it is in the true developer mode," the seller 'kimberlyk1018' writes. "There are no FCC markings on the rear of the device or a model number. This is the real deal!!!!"
The seller also says the Lightning port is red "which is a sure sign of a prototype". They can't guarantee the device will make calls or that the camera will work. But they repeat that it's a 64GB iPhone 6 prototype that US network Verizon sent out by mistake.
It comes with the box, headphones, wall charger and all the paperwork.
In the photos, the phone is running a diagnostic mode which Apple uses to test the functions of the device.
At time of writing it has reached $61,300 in bids – an insane amount of money for a device that's next to useless – and there are still three days to go.