Bicycle horn and bicycle anti-theft alarm - two in one Bicycle horn with anti-theft alarm function The bicycle horn is an 80 decibel bell at 130, which can automatically adjust the volume and has an anti-theft alarm function.The bicycle bell will make a shaking sound, which is to detect the anti-theft sensitivity, which is normal.IPX6 waterproof Even in a storm, you don't have to worry that the bike horn will be damaged.Still working.Multi-functional buttons 1. Enable bell mode and anti-theft mode. 2. Bell mode: the first button is volume up, the second button is the default ringtone, and the third button is volume down.(During driving, when you need to honk, you can press three buttons to make a sound) 3. Anti-theft mode: press and hold the third button for 3 seconds to enter the anti-theft state.When placed as it is, it has three levels of sensitivity.Long press the first button to unlock the anti-theft status.USB charging The red light indicates that it is charging, and the green light indicates that it is fully charged.Bicycle warning with anti-theft alarm The bicycle is equipped with an anti-theft alarm function, which can remind others and your own bicycle that it is in danger and reduce the risk of theft.(try to put the bike 100 meters away from you) In anti-theft condition, three-level sensitivity At different sensitivities, the sound mode can be adjusted.It can be adjusted according to your own usage habits.Bicycle horn packaging details Bicycle bell, USB cable (without charging plug), manual.Small and light, easy to install.Suitable for handlebar diameter 0.86"- 1.25" ( 22.2- 31.8mm) Suitable for mountain bikes, road bikes, scooters, electric bikes, children's bikes, motorcycles, etc.