GAMPRO 12V-24V 102dB Heavy-Duty Backup Warning Alarm with Super Loud Beeper Tone for Truck Van Freight Car Lorry Heavy Vehicles Produces a powerful beeping sound that is 107 decibel, it will be louder in practical use. Automatically adjusts to a voltage range of 12-80 volt vehicles,Waterproof housing with epoxy embedded electronics. Wiring is required to any 12V-80V DC power source. Preferably your reverse backup bulb wire. Universal mounting bracket with slotted holes. It can be mounted anywhere in your heavy-duty vehicle. Easy to install. Back-up alarm is made for heavy-duty & commercial use, best for Trucks Van Freight Car Lorry Heavy Vehicles.