I may have mis-read the original post re the cable.
I was of the impression that the OP wanted the "length" to get to
the cigarette lighter power output. That being the case, they would need
one of these....(sorry but I can't seem to get the link to post like a "link")
http://www.massiverc.com/Shop/en/148-mini-usb-car-charger-adapter.html
Obviously yours is a "hard wire" application.
I am still planning on moving the cam from one vehicle to the other until it
proves inpractical. I will hard wire the primary & use the cable & adapter in the second vehicle.
Edit: Oh, thank goodness - it shows as a "link" when I hit post reply