The Master Lock Magnum Laminated Padlock features a 51mm wide laminated steel body for maximum strength and reliability, and is surrounded by stainless steel and zinc outer components for weather resistance. The 10mm diameter octagonal shackle is 25mm long and made of Tough-Cut boron-carbide which is 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.