1: ABS+PC material, durable 2: 120dB high decibel horn warning sound, effectively remind pedestrians and vehicles 3: No tools required, more convenient installation. The elastic silicone band is versatile and not limited by the thickness of the handlebars 4: Elastic silicone belt, firmly locked on the bike, not afraid of bumps and extreme road conditions 5: Suitable for mountain bikes, road bikes, scooters, children's bikes, etc Type : Electric HornMaterial : Engineering plasticsModel Number : CBH3Certification : CESize : 68*63*53mmName: Bicycle electronic horn + anti-theft deviceMaterial: ABSDecibel: 120dBWaterproof level: IP65Battery: 200mah internal batteryColour: blackFeatures; 120dB electronic horn, anti-theft functionApplicable car shape: road bike, mountain bike, scooter, children's car (bicycle handlebars can be installed within 3.5cm in diameter)