A "no ball" whistle based on the whistles owned by the US ARMY. Made of non-toxic, durable ABS. Perfect for transmitting sound signals - alarms, commands etc. Non-slip texture enables to use the whistle in various conditions, e.g. on the military training area or in military training area or a sports field. Can be hanged around the neck or attached to any part of clothing. A "no ball" whistle is a perfect offer for instructors, globetrotters and fans of outdoor.