The Master Lock 1514D Dial Combination Lock is best used indoors to secure gym lockers and school lockers. Dial lock features a preset, three-digit combination lock for keyless convenience. The 1514D locker lock is constructed with a metal body, stainless steel cover and hardened steel shackle. An anti-shim locking mechanism is included for added strength and security. Lock shackle is 3/4 in. (19 mm) long and 13/16 in. (21 mm) wide. This Master Lock combination padlock is not intended for outdoor use. Master Lock's Limited Lifetime Warranty provides peace of mind from a brand you know and can trust.