Four Horn Modes with Remote ControlBicycle ringtones include whistle, horn, siren and buzzer. You can choose the ringtone according to your preference. (Long press button 2 to change the ringtone.) Bicycle horn 80-120dB, automatically adjust the volume. (Click the + button to increase the volume. Click the - button to decrease the volume.) Security and Anti-theftClick the button in the upper right corner for 5 seconds to enter anti-theft mode. Switching to the anti-theft state has a three-level sensitivity function; short press the unlock button to exit the anti-theft state. The speaker has a built-in anti-theft sensor, and it is normal to have parts inside the speaker. IP66 Waterproof and USB ChargingHigh-quality IPX6 waterproof electric bicycle horn, can be used in rainy days, extremely convenient and practical for daily use; The electric bicycle horn alarm uses USB charging (charging method: charging socket, power bank, laptop. ) Super Long Battery Life, Super Long Standby TimeThe bicycle horn can be recharged via USB and can be recycled. The built-in 250mAh battery is fully charged in about 1.5 hours, can be reused 1000-1500 times, and has a working time of 20-30 days. (The charging light turns green to indicate the battery is fully charged.) Easy to InstallEasy to install, connect the bike horn siren and remote control to the handlebars. The upgraded silicone bands are durable and secure so they are safe to use. The horn can be installed on all kinds of bicycles Packaging list: 1* car bell Note: 1. Please allow some errors due to manual measurement. Please make sure you don't mind before bidding. 2. Due to different monitors, colors may vary, please understand.