Great for referees, coaches, lifeguards, trainers, police, personal use and more. The Champion Sports Electronic Hand Whistle makes it easy to distinguish between different alerts for your needs. The combination power and volume switch easily slides to the desired position. Attach the included wrist strap to the whistle for easy retrieval while on the go. Three volume selector Three tone selector Push button activation Adjustable wrist lanyard included The sound can be aimed in any direction Three AAA batteries are included