A loud whistle, made from a toughened plastic material, this non-corrosive whistle is an excellent safety device for backpackers, scuba divers, skiers, sailboarders and water skiers, in addition to many other outdoor activities. This emergency whistle as an essential part of any outdoor or mountain survival kit, can be used to alert people if you are in distress. The internationally recognized distress signal is 6 blasts of the whistle with a 1 minute break and then repeated. The reply is 3 blasts with the same pause. The high pitch sound from this product is significantly louder than convention ones. Made of durable, lightweight molded plastic built in clip, so you can attach it almost anywhere.