It is a high-sounding, 3-branch melody horn with 3 compressor-powered pipes. 12 Volt can be used in all vehicles; automobiles, commercial vehicles, boat etc. It is a loud A quality product. It has a red hard plastic snare drum pipe. It produces melodious sound in combination by connecting to each other with hoses. It has its own compressor. For proper operation of the product, use a relay. Features 1st pipe: 20.5 cm 2nd pipe: 15.5 cm 3rd pipe: 14.5 cmHigh tone: 840 HzMid tone: 795 HzLow tone: 630 HzPackage content: 1 compressor 1 three-outlet air pipe 1 on/off switch 1 Relay + Connection diagram 3 Snare pipeConnection screws and apparatus70 cm air hose.