The Master Lock Magnum number M1XTLJ Laminated Padlocks feature a 1-3/4 in. W (44 mm) laminated steel body for maximum strength and reliability and is surrounded by stainless steel and zinc outer components for weather resistance. The 5/16 in. Dia (8 mm) octagonal shackle is 2-1/2 in. L (64 mm) and made of Tough-Cut boron-carbide, 50% harder than hardened steel, offering maximum resistance to cutting and sawing. The 4-pin cylinder prevents picking and the dual locking ball bearings provide maximum resistance against prying and hammering. The Lifetime Guarantee provides peace of mind from a brand you can trust. Features: Magnum #1 choice of professionals 2-1/2 in. (64 mm) shackle clearance for more uses Dual-armor protection: 1-3/4 in. (44 mm) laminated steel core for strength surrounded by stainless steel and zinc outer components for weather resistance Reinforced body bumper for scratch resistance 4-pin cylinder for increased pick resistance Keyed alike - same key opens both locks Lifetime guarantee