Professional Quality, manufactured from chrome vanadium electric steel, oil hardened & tempered, with smoothly ground jaws, joint faces & an accurately formed box joint with safety stop. The parallelogram-shaped gripping surfaces have specially hardened teeth to 61HRC for positive grip on pipes & nuts. Plastic coated handles with slip guards for extra safety. Has 'no-nip' feature which prevents handles locking together & damaging users' hands.