The Master Lock No. 1592 3-digit shrouded combination padlock with key control feature for supervisory access includes many enhanced security features, like a shackle shroud to prevent shackle cutting or shimming, the exclusive BlockGuard® Anti-Shim technology, a hardened steel shackle and double-reinforced stainless steel casing. Designed to fit lockers with a padlock eye of at least 5?16in (8mm) diameter, these locks provide multiple customization options to fit your needs.