The Master Lock No. 312D Laminated Padlock features a 1-9/16” (40 mm) wide laminated steel body for maximum strength and reliability. The 9/32” (7 mm) diameter shackle is 1-1/16” (27 mm) long and made of hardened steel, offering extra resistance to cutting and sawing. A blue weather resistant thermoplastic shell is designed to add protection against moisture, dirt, and grime. The 4-pin cylinder prevents picking and the dual locking ball bearings provide resistance against prying and hammering.