Aquatec Balanced Power inflator with integrated Underwater Horn Standard Power Inflator w/ built-In underwater Horn - Can be used to retro-fit most BCD's. Horn works both UNDERWATER and on the SURFACE. Volume: Approx 120 DB. (Above water range approx 0.5 - 1.0 mile, very loud above water. Keep away from ears at all times.) Requires just a tiny bit of air to activate the underwater horn. 1" Dia. filler hose