Laminated Padlocks feature a 1 9/16 inch (40 mm) wide laminated steel body for maximum strength and reliability. The 3/4 inch (19 mm) diameter shackle is 1 inch (25 mm) long and made of hardened boron alloy, offering maximum resistance to cutting and sawing. The 4 pin cylinder prevents picking and the dual locking ball bearings provide resistance against prying and hammering