The kryptonite kryptolok series 2 d lock has a 13 mm hardened kryptonium steel shackle and a patented deadbolt locking mechanism for extensive holding power this kryptonite bike lock will offer you quality security for moderate to high crime areas and also has an offset key location and overhead cam locking mechanism to resist leverage attacks kryptonite kryptolok series 2 d lock features 13 mm hardened kryptonium steel shackle patented deadbolt locking mechanism for extensive holding