Contactless Electric Whistle: The hand button whistle avoids mouth contact and requires no blowing to produce sound, making it ideal for use by multiple people, It offers a loud, clear and easily recognizable sound, Perfect for referee, coache, PE teacher, outdoor camp, sports events, traffic guides, pet train, and emergency self-defense Portable Whistle: Designed with a streamlined body for easy grip and comfortable use, It comes with a lanyard, allowing you to easily attach it to backpacks, camping gear, or carry in pockets, belts, or shoulder straps for quick access Long Life Whistle: Made from durable, impact resistant ABS material, it is nontoxic, odorless, and safe to use Additionally, the whistle for teachers comes with four replaceable CR2032 batteries, allowing for quick replacement and eliminating the hassle of long charging times If the sound weakens, simply replace the batteries Color: Black and Red Material: ABS Package Contents: 1xElectronic Whistle Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.