jammers are beautiful, but the thing with them is if it scrambles the signal sent to you its legal, but if it transmits its illegal. i have a rocky mountain jammer and what it does is takes how fast you are doing and adds and subtracts to it rapidly, so if your doing 75 the cop will see somthing like 75, 68, 80, 74, 59, 63 they wont get a lock. i like mine, i got it around july 4 when all the cops are out ticketing, so i thought id be a flagrant moron and do a little speeding around 270 near dublin, and at 15 over i didnt get a second look from the cops.