Sturdy and Durable: Heavy duty bicycle U lock is made of hardened max-performance steel shackle resists cutting and leverage attacks. More Safe: Mountain bike locks sing zinc alloy lock core and complex serpentine key slot to against various means of theif effectively. Increased Protection: Bike U-lock combin with steel loop cable can provide increased protection for securing front wheel or accessories. With 4ft high-quality steel cable allows greater locking flexibility. For bicycle, motocycle, electromobile. Design & Performance: Silica gel layer coated protect the d-lock bike lock prevent scratched. Waterproof bike lock with mounting bracket, no extra packing required. With 2 Keys: Bike lock set with 2 pure copper keys, so you'll always have a spare. No trouble forgetting the password.