How old is it and is there any wiring (relay) that comes with it ..?
It is probably a year and a half old...relay is built into the case assembly. The only wire required would be a fused wire from the battery and the two stock wires.
Free bump for an outstanding horn. I bought this same one these used 2 years ago...it took a bit of getting used to the size of it, but the first time it saved my life...I got used to it real quick. I have hade to replace the relay once ($2.25 at autozone) when I first got it...problem free since then.
Would never consider taking it off the bike...at 130db, it's a real head turner - even for a car going 85 mph!!!