The Aqua Marine Rescue Whistle is powerful, rugged and reliable. Designed for extreme conditions in the toughest marine environments this whistle is suited for any environment. Made from high-impact, heavy duty plastic here in the U.S.A., there are no metal or moving parts to break or corrode. The ultra-loud, two chamber design allows for the highest sound possible. The built-in clip allows for placement virtually anywhere and with the lanyard hole you can strap this whistle to any piece of gear. Perfect for the track coach, swim coach and everyone that ventures outdoors. We hope you'll never need to use it, but in an emergency you're sure to know it works. Don't settle for a cheap knock-off. Get one for everyone you care about. Choose from Single Packs to 1000 Packs.