FOR SPORT YA Professional Sport Electronic Whistle with Lanyard, Ultra Loud Sound and Long Battery Life - Perfect for Outdoor Sports, Coaches, Referee, Gym Teachers, Lifeguard and Emergency ULTRA LOUDNESS. 125 +/- 5dB loud sound is created at every blast. LONG BATTERY LIFE. 4 CR2032 batteries produce over 5000 blasts. 2 TONES SELECTABLE. 2 different tones available on one whistle. IMPROVED HIGIENE. Hand operation on electronic whistle instead of mouth blown. MULTI-USAGE. Ideal for outdoor sports, coaches, referee, gym teachers, lifeguard and emergency