Compact size Loud Air Horn. Can fit easily on a Boat, Motorcycle, Car, Truck, Van, SUV, or Motor home. Works with any 12 Volt electrical system. The compact size allows it to be easily installed in any tide space under the hood or to your existing horn mounting location. Water and weather resistant. No air tubing to hook up, no separate compressors to install. It's all included in this compact unit. Made of rugged steel compressor and high impact resistant plastic construction horn. Loud dual tone high/ Low sound. Includes air compressor and twin tone air horns, all combined in one compact unit. Comes with a mounting tab, hardware kit, horn relay and installation instructions. Horn dimensions: 5" long x 4-1/4" deep x 3" wide.