FEATURES [Safety Function(3 Volume Levels)] - The bike horn (adjustable volume, 80dB-130dB) is loud enough to alert anyone or even people in a vehicle to your presence, ensure your safety during riding. (Press button 2 to open the ring, press button 1 to increase the volume, press button 3 to decrease the volume). Perfect bicycle accessories for you or your kids. [Anti-theft Alarming (3 Sensitivity Levels)] - If anyone touches or pushes the bike, the alarm will emit a rapid and continuous loud alarm. This bike alarm has 3 levels of sensitivity anti-theft function. press button 3 for three seconds to enter the pre-alarm state, press button 1 to close the anti-theft. [USB Rechargeable Long Battery Life] - The bike horn bell with a USB port to fit the power bank, charging plug, and laptop USB. After 1.5 hours fully charged, a 250mAh battery can be used for 20-30 days. [Easy to Install Remove] - Easily mounted and secured with the stretchable straps to fixed on the handle, install or release it from the bike handlebar within 20 seconds. Suit for 0.86"-1.25"(22.2-31.8 mm )diameter bicycle handlebar. [IPX6 Waterproof ]- This bicycle rechargeable horn can be attached to mountain bikes, road bikes, walking bikes, electronic bikes, or scooters, which is IPX6 waterproof which can be used on rainy days. Bike Horn Bike Anti-Theft Alarm -- Two in one Wide Application * The alarm bell is a 130dB high-decibel bell with large vibration and anti-theft alarm. * The sound of the electric horn is the same as the horn of a motorcycle, but is different from the bell of an ordinary bicycle horn. * Suit for 0.86"-1.25"(22.2-31.8 mm )diameter handlebars of Mountain Bikes, Road Bicycles, Scooters, electric bicycles, children's bicycles, Motorcycles etc