IRWIN Record Arm Adjusted High-Tensile Bolt Cutters have jaws that are specially heat-treated for cutting very hard materials up to a hardness of Brinell 500 (Rockwell C52, 110 tons/square in). The centre cut jaws have a short nose for trouble-free cutting of pre-stressed concrete reinforcing rods, mesh and wire, high-tensile steel rods, bolts and case hardened chain, cold drawn alloy steel and tempered sprung wire.IRWIN Record 918H Arm Adjusted High Tensile Bolt Cutter 460mm (18in).Overall Length: 460mm (18 in).Max Cutting Capacity: 6.4mm (1/4 in).