With pierced hinge, so that both parts of the gripping jaw always remain stable against each other. 7-way adjustable for tubes Ø 1/8 - 1.1/2 inch. Chrome-Vanadium-Electro steel, oil-hardened. Black atramentized with polished jaws and hinge. Legs red plasticized. Gripping surfaces with specially hardened teeth, hardness approx. 62 HRc. Self-locking on pipes and nuts, no slipping of the workpiece. Protection against finger clamping.