The Master Lock 3SST Stainless Steel Padlocks with Key feature a 1-9/16 in. (40 mm) laminated stainless steel body design, with a tough weather coated finish for maximum strength and reliability. The 9/32 in. (7 mm) diameter shackle is 3/4 in. (19 mm) long and made of stainless steel, offering extra resistance to cutting, sawing, and weather. The 4-pin cylinder prevents picking and the dual locking ball bearings provide resistance against prying and hammering. The Lifetime Guarantee provides peace of mind from a brand you know and can trust.