Mini bicycle alarm system: 46mm x 46mm compact anti-theft device that saves space. Made of PC and anti-UV material, IP54 rated for waterproof and dustproof performance, resistant to high and low temperatures, suitable for outdoor use in all weather conditions. Easy to install wireless alarm system with multiple mounting options including brackets, cable ties, and double-sided adhesive tape—no wiring required. Compatible with bicycles, motorcycles, scooters, tricycles, and cars. Durable bicycle alarm system with remote control. Host features a built-in 700mAh lithium battery with USB-C charging and low battery indicator, eliminating the need for frequent battery replacements. Enhanced energy-saving technology ensures extended battery life for the remote control. Loud and multifunctional anti-theft alarm with 6 automotive-grade alert tones and a maximum volume of 110 dB, providing effective theft deterrence. Three ringtone options can be adjusted remotely. One-button arming and disarming for convenience. Remote control helps locate vehicle easily. Highly sensitive theft protection with 3D motion sensor and advanced algorithm to accurately detect unauthorized movement and reduce false alarms. 7-level sensitivity adjustment. Alarm triggers immediately upon touch, tilt, pressure, or impact. Suitable for use on bicycles, doors, windows, and other applications.