This USB charging electric horn bicycle bell features a clear and gradual treble for a wider directional emission range. It is suitable for all handlebars, can be easily installed in 2 seconds, and has a stable installation with a rubber ring that can be adjusted in two steps to fit various types of bicycles. The fully sealed design and triple protection ensure it can withstand harsh conditions. Its compact design allows it to be hidden inside the handlebar without affecting other operations. It has built-in 280mAh lithium battery with a long standby time of 180 days and can continuously ring for 4,000 times on one charge. This bicycle horn is a must-have accessory for a safer and more enjoyable ride. Features 1. Clear Sound: The sound is not sharp enough but clear. The gradual treble is not harsh and the directional emission range is wider. Size: 4.9x6.6cm, Suitable for all kinds of handlebars from 22 to 31.8mm in diameter. 2. Suitable Handlebars: The electronic bicycle bell is compatible with all kinds of handlebars, can be fixed on the handlebars in 2 seconds. The rubber ring can be adjusted in two steps with a stable installation, which is suitable for various types of bicycles. 3. Fully Sealed Design: The fully sealed design without fear of storms and full triple protection design to meet daily use in harsh environments. 4. Compact Bell: The watch can be hidden inside the handlebar without affecting the handlebar brake shift or other bracket operation. 5. USB Charging: The electronic bicycle bell is USB charging with high-quality polymer battery. With built-in 280mAh lithium battery and equipped with standard USB charging for Android, the electronic bicycle horn features long standby time for 180 days and 4,000 continuous ringing for one charge Specification Material: ABS+PC Color: Blue Red Pink Green Black Rose Size: 4.9 x 6.6cm Package Includes: 1 x Bicycle Electric Bell 1 x Rubber Cable Tie 1 x Charging Cable 1 x Instruction All Products From Us Have Undergone Strict Quality Checks. If There Is Any Quality Problem Or You Are Not Satisfied With The Product Contact Us. We Will Give You The Best Solution.