Binboll Double-Tube Whistle Aluminum Alloy Survival Whistle for Outdoor Needs Sports Referee Emergency Premium Quality: Aluminum Alloy Material, durable. Light Weight: Only 12g, easy to carry. Loud Whistle: Double-tube design, 120db, high-frequency. The whistle has no built-in pea ,so it will not mold and breed bacteria because of the pea.Can be used in rainy days. Versatility: A good item for outdoor needs, sports referee, emergency. Weight :Only 12g(0.42oz) Material: Aluminum Color: Gold/Silver Sound Volume: 120 db Size: about 2.2 x0.6 in