The octagonal shackle is made of Tough-Cut boron-carbide, 50 percent 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 covered keyway offers maximum weather protection, and reinforced body bumper protects against scratches. This padlock is perfect for self storage units, sheds, trailers, moving trucks, vans and more. The Limited Lifetime Warranty provides peace of mind from a brand you can trust.