Wolo (416 Euro Emergency Vehicle Horn - 12 Volt, Two Tone Super loud, air powered two tone horn With the throw of a switch you can change the sound of the horn from a Steady Blast to a Euro Emergency Vehicle HI/LO sound The two trumpets are metal, chrome plated and will look great in any engine compartment Comes with a heavy-duty compressor, 30-amp relay, hose, toggle switch and mounting hardware