Hardened chrome vanadium steel jaws and thumbwheel adjustment. Heat-treated aluminium alloy handles for maximum weight advantage whilst maintaining tensile strength of conventional cast iron or steel handles. Corrosion-resistant rippled powder coating. Exceeds the requirements of the American GGG standard for safety and durability. Firm and fast self-clamping; secures hold on the smoothest pipework. For use on pipework and fittings.