The Master Lock 875D Heavy Duty Outdoor Combination Lock features a 2 inches (51mm) wide zinc body for strength and reliability. The 5/16 inches (8mm) diameter shackle is 1 inches (25mm) long and made of hardened steel, offering extra resistance to cutting and sawing. The roller pin mechanism provides MAX protection against attacks. The shackle seal offers superior weather protection. The lock includes set your own combination convenience, without the need for a reset tool. The 4 digit dialing allows for thousands of possible numeric combinations. The Limited Lifetime provides peace of mind from a brand you know and can trust.