The 12mm hardened steel, standard size Combination U-lock provides high security against theft. This combo u-lock includes an easy to use 4-digit resettable combination and no keys for you to lose! This is a standard size u-lock at 4" x 8" which is great for many lock-up scenarios. The Combination U-lock has optional $500 Anti-Theft Protection Offer (registration required) and includes the Kryptonite Combo Safe Program. Register your combination with us at and we'll be able to help should you forget your combination.