[Quality materials] - Made of food grade stainless steel, safe, smooth surface, corrosion resistant. [Wide application] - Our whistles are very practical, suitable for referees, trainers, training, instructors, sports, lifeguards, teachers, defense, survival, emergency, herding, bird or dog training, etc. [Easy to use ] - each whistle comes with a black wrist strap, you can easily install it around your neck. [Loud whistle] - the whistle of a crisp and clear sound, you can quickly catch the crowd’s attention whenever you want. [Size] - 4.521.4CM stainless steel whistles,