Description: 【Premium Material】: This alarm U lock is made of alloy steel, which is wear resistant, waterproof, and sturdy. It's designed to withstand harsh weather conditions and provide long term security for your vehicle. 【Built in Motion Triggered Alarm】: The motorcycle lock features a built in motion alarm that emits a loud sound when the lock is hit shaken. This combines locking functionality with an alarm system for enhanced security. 【Portable and Compact】: Compact design, small size, easy to carry, frees hanging on handlebar/seat/frame or placed in a bicycles storage bag. 【Comes with Accessories】: The package includes 3 keys and 6 spare batteries, ensuring you always have access to your bike and the alarm system remains functional. 【Versatile Use】: This U lock is ideal for various vehicles such as bicycles, motorcycles, electric bikes, etc, providing strong protection against thefts. Specification: Material: Alloy Steel Color: Black Total Size: 13.8cmx16.7cm/5.43inchx6.57inch U Shape 11.4cmx10.2cm/4.49inchx4.02inch Base 13.8cmx4cm/5.43inchx1.57inch Package Includes: 1X Alarm U Lock 6 Batteries 3 Keys Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful on-line shopping!