I recently installed an air horn on my RIII Touring and it is LOUD! installation was fairly straight-forward using a relay in the circuit. I hate the puny-ass horn that Triumph thinks is adequate for American hiways, but it can't be heard for **** over freeway noise. They will definitely hear this! The compressor is mounted behind the last exhaust header. The black horn is sort of hard to see...sorry!
Several of us have installed those. I was impressed the first time I saw one on @Kevin frazier 's bike, and I soon followed suit. Ours are mounted on the left side.
No Batteries Required! No Doctor Prescription Easy Installation! Insert Only Small End Into Ear! Left Or Right Ear Compatible! No Complex Wires Required! No Charging Required! Light Weight and Easy To Transport!