Made of high-quality metal that provides corrosion protection, wear resistance, and durability. Easy and convenient to install, suitable for securing bicycles. Features a highly sensitive defense probe with microcomputer control for high reliability, sensitivity, and enhanced security. Precisely triggered by unauthorized movement or tampering. Specially designed for bicycles to help ensure bike safety. Compact and lightweight design for easy portability. Vibration and disassembly trigger a 110 dB alarm to deter theft or burglary. Press the "Lock" button to activate the alarm system after a beep; the alarm will sound when vibrations are detected. To deactivate, press the "Unlock" button. The system disables after two beeps, allowing normal bike use.