A great Anti-Theft Device that allows you to handle emergency situations without the fear of someone driving away with your vehicle. When the switch is turned on the system allows you to remove the key from the ignition switch while your vehicle is running. This allows you to continue to operate life support equipment, run your lights, air conditioning or heater so you can leave your vehicle to handle emergency situations. Any movement made to the brake pedal and shift lever will kill the engine and prevent anyone from driving away with your vehicle.