Our electronic hand-operated whistles make it easy to use with just the press of a button! Hand-held whistle without any mouth contact, avoid hygiene problems caused by droplets, there’s a lower risk of transferring germs from person to person. Sanitary, healthy and safe!With 2000mah Lithium large capacity batteries, enables it to create strong and consistent sound. The whistle can last for 15000 blasts, continuous work for over 4 hours. USB charging, convenient and easy to use. You don't need to buy and change batteries anymore.Three switch three tone function design. Three distinct tones personalized electric whistle with whistle sound, siren sound and horn sound. 120dB-150dB power sound, the volume can be adjusted according to the demand. You can choose the best sound mode and volume for your purpose. In addition, it with LED flashlight, can be used for lighting and SOS, suit for outdoor and emergency assistance.Heavy-duty plastic construction makes the whistle long-lasting. Our whistles are great for all sports events & sports games. Perfect for all kinds of people (coach, referee, sports training, teachers, team leaders)Perfect size hand-held whistle(size: 5.2inch×1.5inch, weights about 97g). It comes with a long 19.5inch lanyard, which can easily loop through backpack, sailboats, camp hike gear, life jacket, kayak PFD. You can also tie the whistle to your belt or shoulder straps and hanging on the neck.Decibel: 120dB-150dBSound mode: 3 tonesVolume adjustment: each tone sound has 3 volumesBattery charge: 5V 1ABattery capacity: 2000mAh rechargeable 18650 lithium batteryLed light function: lamp single, night lightWhat’s included:Electronic WhistleLanyardInstructionUSB charging cable