Multifunctional Bike Bell 4 kinds of soundone button switching. IPX5 level waterproof + Anti-dust + Shatter-resistant. Fully satisfy your outdoor cycling needs.USB ChargingWith rechargeable 200 mAh lithium battery, USB cable charge 1.2 hours full charge. It can ring the bell for 2000 times continuously enough to work 20-30 days.Loud and ClearThis Horn Loud Volume can reach 125db which is loud enough to alert anyone or even people in a vehicle to your presence. Perfect bicycle accessories for you or your kids.Anti-Theft DesignLong press the tail switch to turn on the anti-theft function. When someone moves the bicycle, the horn will sound an alamrm for 15 seconds, When it is triggered again, the alarm will still sound, The alarm can be released only by long pressing the tail switch.Easy to Install & RemoveTools free, simply put the bike bell to the handlebar ( Diameter 22.2 -31.8mm) and use the silicon buckele to fasten it, suitable for road bikes, mountain bikes, kids bikes, city bikes or other types.