This is the Giant SureLock Tough 1 Cable Lock.Bike locks provide deterrent to bike theft, however no lock is theft proof. Please research both your area you plan to lock the bike, amount of time and time of day, and then which lock best suits your specific needs. Remember that locks may seem expensive, but a new bike is always more. Features: X2P double bolt locking mechanism for added security Double-locking hardened steel 11mm (0.43") shackle provides maximum security 8mm (0.32") titanium enforced hardened square steel chain links for high cut-resistance Z-cylinder is more reliable and user-friendly than ever before, prevents key from turning before being fully inserted into the cylinder Nylon chain cover prevents scratching and allows for compact storage: throw it over your shoulder High security, pick and drill resistant lock cylinder Includes 3 standard keys with over 30,000 key variations