40% lighter then comparable cast iron models. Jaws and all other parts identical to the cast iron models. Heel jaw properly seated so as to prevent load on pin. Hook jaw forged and dual heat treated. Knurled and tempered adjusting nut. Set of flat and coil springs which assure instant grip of the pipe and a perfect ratchet action. Meets U.S. specifications GGG-W-651 Type 1 Class B.