The Masterlock Discus features a tough-cut octagonal boron-carbide shackle that's 50% harder than hardened steel. Its 3-1/8in (79mm) wide stainless steel body provides maximum weather resistance. The fully shrouded design minimizes shackle exposure, protecting against bolt cutter attacks. A reinforced body bumper offers scratch resistance, while the 4-pin cylinder increases pick resistance. The covered keyway provides maximum weather protection, and the key retaining feature ensures the padlock is not left unlocked. The Masterlock Discus comes with a lifetime guarantee.