Fangrui Product Details Fangrui Product Details Fangrui Product Details Usb Rechargeable, No Battery Required - The Bicycle Alarm Is Powered By A Built-in Rechargeable 4.2v 700mah Lithium Battery, Which Can Be Charged Via A Dc5v Power Adapter, The Package Includes A Usb-c Charging Cable, No Need To The Battery And Save Money. The Bicycle Alarm Adopts Version 4 Energy Saving Technology And Can Work For 1~3 Months On A Full Charge (depending On The Frequency Of The Alarm). 3 Mounting Methods For More Uses - Comes With Mounting Brackets, Cable Ties And Double-sided Tape, 3 Mounting Methods. Bracket Installation Is More Convenient To Change The Installation Position. Zipper Ties And Double-sided Tape Are Installed, Suitable For Irregular Installation Items. Easy To Install And Use. Bicycle Or E-bike Or Motorcycle Owner Must Have Anti-theft Alarm. Adjustable Volume And Adjustable Sensitivity - Loud Alarms Up To 110 Decibels Effectively Scare Away Potential Thieves And Give You Peace Of Mind. Well Made Bike Siren With Great Performance. 3-level Adjustable Volum