High-volume electric bicycle horn -- The maximum sound of the bicycle speaker reaches 120 decibels. When riding in a noisy environment, complex road conditions are prone to collision. This oversized horn sound is loud enough to effectively alert the surrounding pedestrians and drivers to avoid traffic accidents. Anti-theft alarm -- Press the left button (lock button) for a long time to enter the alert state. If anyone touches or pushes the bicycle, the bicycle alarm will immediately make a loud and continuous alarm sound, so that thieves dare not approach. Press the right button (unlock button) for a long time to leave the anti-theft state. Long standby time -- Electric bicycle horn alarm, the built-in horn capacity is 250mAh. It can be fully charged within 0.5 hours, can be reused 1000-1500 times, and work for 20-30 days. A charge can be used for a long time, you don't have to worry about running out of power next time you use IPX4 waterproof and USB charging -- The bicycle bell is waterproof and can be used in rainy days. The electric bicycle horn alarm adopts USB charging and can be charged in various ways, such as outlets, power banks and laptops. Easy installation -- The doorbell does not need to be installed with complicated tools, just attach the silicone bicycle horn alarm strap to the handle, and the strap is elastic and durable. This bell is suitable for bicycle handlebars with a diameter of 22.2-31.8mm, which can be applied to mountain bikes / electric scooters / racing cars, etc. Material: ABS, Specifications: horn 6.5 * 3.5cm strap 6.8 * 2.5cm, not just horn or anti-theft alarm, Waterproof IPX4, battery 200MAH, Volume 120 decibels: outdoor can penetrate 500 meters, Accessories: speaker * 1 + strap * 1 + USB data cable