It provides maximum strength for the body of the padlock. Offering the maximum in strength, weather protection, and versatility, its easy to see why Magnum is the number one choice of professionals. This lock is ideal for use with residential gates and fences, sheds, workshops, garages, storage lockers, tool chests and tool boxes. Dual Armor Protection: Laminated Steel Core for Strength, Stainless Steel and Zinc Outer Components for Weather Resistance. Magnum 2" Laminated padlock with 2-1/2" boron shackle With dual armor construction & stainless steel protection Ball bearing locking for maximum pry resistance Tough-cut octagonal boron-carbide shackle 4-pin cylinder for added pick resistance Uses master lock key blank k1box.