Nearly 40% lighter than comparable cast-iron models of the same size. Sturdy, cast-iron housing and I-beam handle for comfortable grip and strength without excess weight. Full floating forged hook jaw with spring suspension for instant grip, instant release. Replaceable jaws with tough, heat treated, high-alloy steel jaw teeth. Rugged, easy-spin, nonstick adjustment nut that automatically cleans grime fro hook jaw shank. Uniquely braced, extra-strong mount for heel jaw. Jaws and all other parts identical to Heavy-Duty Wrenches. Also available with special hook and heel jaws for plastic coated pipe.