I like the sound of air horns on a Semi or Train but real estate is limited for flutes and a compessor. I also wanted it to run off my existing horn wiring, or so I thought. I found a guy that put together a set of 4 horns from old Cadillacs and Buicks. Each horn plays a different note forming a musical chord distinctive of a train, Cadillac or something larger than a scooter.