The Master Lock Magnum M40XKAD Discus Padlock features a 2-3/4 in. (70 mm) wide stainless steel body for maximum strength, reliability and corrosion resistance. The fully shrouded design minimizes shackle exposure and protects against bolt cutter attacks. The 3/8 in. (10 mm) diameter octagonal shackle is 5/8 in. 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..