Kryptonite Series 2 ULocks made with a 13mm hardened performance steel shackle with classic bent foot design and a patented deadbolt locking mechanism. 13mm hardened Performance steel shackle resists cutting and leverage attacks High security Bent Foottm design for serious protection and great value Patented deadbolt locking mechanism for extensive holding power High security, pick and drill resistant discstyle cylinder Enhanced internal engineering resists twisting leverage