Drop forged jaws with center cut blades, heat-treated for wear resistance and long cutting life. Cuts soft and medium/hard materials (maximum hardness of material to be cut Brinell 300/Rockwell C31). Toggle joints turn 50 lb hand pressure to 4000 lb of cutting pressure. One-piece, aluminum alloy handles with rubber grips. Do not use any cutter on energized circuits, wire or cable.