[ZZCruzr]

IRPT...I'm not a lawyer (thank God) but this is a blurb from their web site...
"Our jammers do not transmit radio frequencies. The radar portion is a receiver not a transmitter. *This is why our jammers are legal! They have an FM chirp, a mixer, and a waveguide antenna for all radar bands the FCC allows the Police to use ( 7GHz - 38GHz ). The lidar ( laser ) portion transmits a specially modulated field of light from the vehicle with infrared diodes that cover all three laser guns in use today. The radar and lidar portions of our jammers confuse the radar and laser guns which prevent a hard reading of your speed. This makes your vehicle electronically invisible to police radar and laser guns. The radar jamming circuit mixes a doppler FM chirp with the incoming police radar signal and reflects it back to the radar gun. The computer in the radar gun must receive eight identical, consecutive readings before it will display your speed. All the different speeds contained in the FM chirp confuse the computer in the radar gun so it does not display any speed. This effect duplicates the normal operation that the officer usually sees. Since it is normal to occasionally lose the target speed, the officer is not suspicious. Reasonable care should be used as flagrant violators could still be caught visually with an estimated speed."

The company is confident enough to say they'll pay any traffic fines the first year.

The thing is a really good detector...so I haven't actually "tested" the jamming part of the story yet!