Kleinn Air Horns Direct Drive Horn System - Harley Davidson Motorcycles is a One Hundred Percent Bolt On, Direct Drive, Dual Air Horn Kit expertly engineered for most Harley Davidson Motorcycles manufactured from 1978 to current. Kleinn Air Horns Direct Drive Horn System for Harley Davidson Motorcycles completely replaces the factory horn assembly and reuses the bike's factory horn cover, ensuring a clean, better-than-factory appearance. Included is a powerful, compact, tank-less direct-drive compressor, a Dual Direct Drive Air Horn, a Custom Bracket proudly made in the USA, instructions for wiring, relay, air line and required Hardware.