Fangrui Product Details Features: Bicycle Security Enhanced: Your Bikes Safety With Our Advanced Bicycle Alarm System. Its Equipped With A High-decibel Alarm That Wireslessly Communicates With A Remote Control, Providing Robust Anti-theft Functionality. User-friendly Versatile: This Alarm System Comes With A Usb Rechargeable Battery, Eliminating The Need For Constant Battery Replacements And Promoting Eco-friendliness. Its Wireless Design Allows For Easy Installation Without The Hassle Of Wiring. Portable Protection: Compact And , This System Is Not Only Limited To Bicycles But Can Also Be Used For Other Vehicles, Offering Broad-spectrum Security. Specifications: Host Built-in Battery: 3.7v 700mah Lithium Battery, Daily Use Lasts 1-3 Months, Continuous Standby Lasts About 6 Months Charging Interface: Standard U Sb-c5 V (some Fast Charging Heads Are Not Compatible) Remote Control Battery: Wl03c: 1 27a (12v) Alkaline Battery For Daily Use For 1-2 Years (counting 5 Remote Controls Per Day) Waterproof Rating: Ip65 Waterproof And