Yes. The wireless that it refers to is wireless transmission. You do need an outlet for power unless you get the battery adapter which last about 4 hours.
The dials that are on the power supplies are for addressing the cameras. Lets say you have 4 cameras, cam1 would be addressed like c1 and cam2 would be c2, c3, c4 etc...
Only one camera can be on at a time. So when the software turns cam1 on it automatically turns cam2, cam3, cam4 off.
You need the cameras, a va11 or va12 usb video adapter, some type of transceiver like a cm15 or cm17 etc..., and some type of video receiver vr36 etc... and then the software to run it on a pc. If you just want to run it on the tv then you can skip the software and video adapter but you would still need like a remote and transceiver like the tm751 to control which camera you want to view.
It all depends on how you want to view and what you want to do. If you tell us this information we could help you on the terms of what you would actually need.