Features:1. Four kinds of sounds are switched by one button, metal bells, whistle horns, tram bells, vibrating bells.2. Add multi-function button group on the back to achieve volume level adjustment and switch function volume 50-100dB.3. The structure upgrade sound is more prominent and the more prominent physical communication structure makes the speaker sound more stable and wider.4. The split type controller is separated from the speaker and installed next to the thumb of the handle to facilitate free pressing and switching.5. Compact design, the size of the watch can be concealed inside the handlebar without affecting the brakes of the handlebars, shifting gears or other brackets.6. USB rechargeable high-quality polymer battery, built-in 280mAh lithium battery.7. Fully sealed design without fear of stormy all three outdoor design, to meet the daily harsh environment.8. It can be fixed on the handlebar in 2 seconds, the rubber ring is adjusted in two steps, and the rubber ring is adjusted. It is suitable for all kinds of bicycle installation.Specification:Battery type: 702025PLBattery Weight: about 6.3gGross Weight: about 77.8gNet Weight: about 48gSize: about 12.3 x 7.6 x 4cm/4.8 x 3 x 1.6inMaterial: ABSInput: 5V 250mAhSound: 100dbSound Mode: 4Package List:1 x Control Switch + Speaker 1 x Strap1 x Charging Cable1 x Manual.Note:Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.