Sincereetali7 Survival Whistle + 1 Survival Whistle: Comes with 7 survival tools: thermometer, compass, survival mirror, magnifying glass, LED light, capsule, nylon rope. Material: The whistle is made of high-strength anti-fall and high-temperature ABS material, which is not easy to broken. Sturdy, durable and wear-resistant, the thermometer and compass scales are clearly visible and easy to read. Easy to carry: about 3.8 inches (about 9.7 cm) in length and 1.1 inches (about 2.8 cm) in diameter, light weight and small size, making it easy to carry. Loud safety whistle, suitable for camping, hiking, cycling, skiing and other outdoor activities, can also be used for training, coaching, sports, teachers, rescue, self-defense protection. In an emergency on the water, a whistle can save your life. The reason is that it is difficult to scream if you fall into the water. In addition, human screams are really not very loud. A whistle is much bigger than a scream, so a whistle is a must when you are in the water. This is the tone you are looking for. Great sound, long distances and will not hurt your ears when playing. Robust and loud. Just the right tone, commanding authority. The inner ball can be frozen in very cold weather. If this happens, try spraying dry silicone inside to spray the ball. I expect this type of whistle to be normal. EASY TO HEAR - 3 super loud survival whistles can produce up to 120 decibels of sound to be heard from long distances and come into play in an emergency.