High db alarm system: Alarm Disc Lock is equipped with a high sensitivity sensor. Once abnormal move is detected, it will immediately make a high db alarm sound(110db)Widely applicable: Disc Brake Lock is suit for various disc brake pads with hole diameter above 7mm, making it not only suitable for road and mountain bikes, but also widely applicable to electric vehicles and motorcycles.Material: Disc Brake Lock is made of quality metal, ensuring the durability of the lock body and providing long lasting protection for the vehicle. At the same time, it has a certain waterproof ability for daily life, and can maintain normal use even in rainy or humid environments.Multi functional: This alarm disc brake lock is designed to be compact, easy to carry and install, and can be widely used in various occasions such as garages, parking lots, streets, etc.Equipped with key: For the convenience of users to open and lock, Disc Brake Lock is equipped with a key. Simple and fast. Specification: Material: Metal Size Chart: 9cmx6.8cmx3.3cm/3.54inchx2.68inchx1.30inch Package Includes: 1 Alarming Disc Brake Lock1 Key1 Instructions Note: Please allow slightly errors 1-2cm differences due to manual measurement.