The Whistler 3400 that is still on its way in the mail is a remote install detector. There is a front radar detector that mounts in the engine compartment, behind your grill. Then there is the remote power source that everything plugs into which is also installed somewhere in the engine compartment or hidden in somewhere inside the car. The final part is the display that gives you the status and projects the sounds. That part can be discretely installed anywhere in your car, like on your dash, beneath your dash, etc.