Innovative design, hygienic and convenient:The electronic whistle completely abandons the traditional oral blowing method, which effectively avoids the spread of and is more hygienic. Just lightly the button, you can send out a loud and clear whistle, saving energy and safety. Its design is suitable for referees, coaches, sports teachers and outdoor enthusiasts and other people, so that you can easily signal on occasions. , cost-saving and multi-functional:The electronic whistle is made of Made of high quality material, it is sturdy and , in addition, it also has LED lighting function, which can provide auxiliary lighting in the dark . The ergonomic design is comfortable for one-handed operation, and the detachable lanyard makes it easy to carry. Equipped with a long lanyard, it can easily go through backpacks,sailboats, camping equipment and so on. You can hang it around your neck, shoulder strap, belt, or backpack, or keep it in your pocket for quick access in an emergency. It also features three speaker adjustments and conversion, etc. to meet your needs. Color: Black Material: plastic not included 2 x AAA batteries Package Contents: 1 x Electronic 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.