Will replace your original horn, or can be installed as an auxiliary horn. Comes with a 3 gallon air tank and 12 volt 200 PSI heavy duty maintenance free compressor. Includes Mounting Hardware, Brass Fittings, Air Tube, Air Valve, 240 PSI Air gauge, 200 PSI Pressure Switch, installation instructions. Ideal for vehicles such as Truck, RV, SUV.