Waterproof dual-trumpet air horns replace stock horn and give a loud warning blast of 128 dBInclude horn assembly, air compressor, relay, simple wiring, cone-shaped dust/bug covers and complete installation instructionsAir compressor creates instant air pressure to the horns and mounts either under the seat, behind right side cover or down tube of frame (mounting position varies per model)Will fit with Harley-Davidson® lowersUse the stock horn button bolt-on, plug-in installationMade in the USA