Finally you know exactly how much room you have behind your bumper. Our reversing system digitally displays the distance between your rear bumper and the nearest obstacle on a readout mounted under the rear view mirror or on your dash. The system also gives you an audibal warning with a beep that intensifies as you draw closer to the object it is reading. With three all weather acoustic sensors you get an accuracy of +/- 1 inch. Available for all model H1 Hummers.