About emergency whistle: This emergency whistle is made of high-quality aluminum for durability and safety. It uses high-frequency dual-chamber resonance and the volume can reach 120 db, and the sound can easily spread far away. Emergency whistle design advantage: This emergency whistle has an excellent airflow design, the surface is anodized for color formation, does not fade, and has a longer service life. And it has no moving parts, no sound blocking parts, waterproof, can be used all day weather, rainy days, wet weather. Versatile: This emergency whistle can be used for camping, hiking, hunting, fishing, boating, cycling and any type of outdoor activity. In addition, it can also be used as a referee whistle, a dog whistle, a security officer's warning whistle and a security whistle for a person to go out alone, especially for girls to go out alone. Convenient and stylish: Each whistle has a key chain that can be easily attached to a backpack or belt, or it can be worn around the neck with a rope, which allows you to whistle quickly. The appearance is simple and generous, convenient and practical, and has a high safety factor. Wearing a golden whistle and a silver whistle is also a beautiful value!