The Master Lock M50XD Heavy-Duty Outdoor Shrouded Padlock with Key, features a 3-1/8 in. (79 mm) wide stainless steel body for maximum strength, reliability and corrosion resistance. Lock is fully shrouded to minimize shackle exposure and protect against bolt cutter attacks. Octagonal lock shackle is 7/16 in. (11 mm) in diameter and is 11/16 in. Lock 4-pin cylinder prevents picking and the dual locking ball bearings provide maximum resistance against prying and hammering. Shrouded padlock covered keyway offers maximum weather protection and reinforced body bumper protects against scratches.