Wireless backup camera

[1gr8bldr]

I am wanting a pair of wireless backup cameras to watch my rear tires while "walking in" fill on garage foundations. But I wonder.... how are they powered? It would not be worth much to think your getting wireless but then have to run a wire for power. Also, looking for a magnetic base? Anybody know anything about these?

 

[Tazza]

I thought they still needed power, but you don't need to run data cables from the cameras to the dash is all.
I actually have a camera for my machine, it's wired i just need time to install it.