No chemicals! No batteries! Just NOISE! The Ecoblast runs on compressed air (obtained via a hand pump) making this the most efficient and economical marine safety or starting device currently available. Powerful 115db sound with built in volume control - Recharge quickly & easily with air from most bike pumps or compressors - Produces up to 70 blasts per recharge - Take it anywhere and it floats - it's super light at only 100grams! • Reliable way to stat a race or stop a game. Works in all weather, in any position. • Safe way to cheer on your team or celebrate a win. No dangerous chemicals or vapours. • Economical and ecological air horn for your boat. Use it again and again and never run out of noise. • Meets U.S.C.G. regulations - always carry a fog signaling device in case of engine failure. Note - Does not come with pump.