The Intekin Bike U Lock Heavy Duty Bike Lock Bicycle Lock, 16Mm U Lock And 5 STURDY: This bike u lock is made of 0.63inch(including 0.1inch silicone cover) carbon structural steel which is cutting-resistant, leveraging-resistant. The silicone cover makes u lock can resist corrosion from dust and dirt to prolong the life of your bike lock. NO BLOCKING: The lock cylinder of u lock is made by zinc alloy blade, which has a precise structure to prevent technical opening. With the lock dust cover and zinc alloy lock cylinder, no need to worry about blocking when opening the bicycle lock. CONVENIENT USE: The bike lock comes with a 5feet renforcement steel cable which is coated with PVC covering, and the whole diameter of it is 0.47inch. With the cable, it will provide your bike with greater locking flexibility and better protection. LARGER SIZE: After receiving customer feedbacks about u lock, NOW WITH LARGER SIZE 8.3*5.7inch bike u lock specially designed for most bikes. Besides, comes with a mounting bracket that is suitable for all circular tripod in diameter ?1.18inch. EASY INSTALLATION: The mounting bracket holder is easy to install, you can refer to our instructions to install it. This convenient installation enables you to store your bike lock quickly when on a ride. Enjoy your beautiful day like never before!