Makes alternating noise for warning pedestrians at speeds below 20 MPH * No installation required * Warns of approaching vehicle from up to 200 feet away * Patent-pending design is the only portable warning device on the market Designed by an electrical engineer's research while working at the General Motors Electronics and Safety Division. Set the magnetic mounted EVWD device on the top of the vehicle, open the door and run the cable inside the vehicle. Plug the device in the 12 volt power outlet. The EVWD Pedestrian Alert System design reduced the sound pressure levels and frequency as compared to AAA Communications electronic deer alert third generation design that originated in 2002. AAA Communications selected 2000+ hertz and a 68+ db noise level for the EVWD Pedestrian Alert System based on multiple studies and the high frequency directional properties. Organizations representing the Blind are pushing for action. The Federal government is passing laws requiring electric cars and electric trucks to have sounds due to safety concerns. Electric vehicle warning sounds are a series of sounds designed to alert pedestrians to the presence of electric drive vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs),and all-electric vehicles (EVs) travelling at low speeds. Their purpose is due to the fact that vehicles operating in all-electric mode produce less noise than traditional combustion engine vehicles and can make it more difficult for pedestrians, the blind, and others, to be aware of their presence.