Easy to Hear - 4 super loud survival whistles can provide up to 120 decibels of sound guaranteed, can be heard from afar, and play their part in an emergency. Not just a whistle : 3 in 1 multifunction, besides an emergency whistle, it is also a compass and a thermometer, bringing you the necessary information during outdoor sports. Sturdy and durable: made made of sturdy, waterproof and durable ABS, easy to clean. Unlike metal whistles, it can be easily hit in very low or high temperature. Compact and very portable: less than 17g, does not bring weight to your outdoor sports, with a lanyard neck strap easy to put on in all situations, it can also be attached to your backpack, belt, etc. Multi-purpose: powerful safety whistle for camping, hiking, biking, skiing, any type of outdoor activities, and also can be used for coaches, instructors, sports, teachers, rescue guards, protection, self-defense.