Professional Quality, manufactured from chrome vanadium electric steel, oil hardened and tempered with smoothly ground jaws, joint faces and an accurately formed box joint with safety stop. The parallelogram - shaped gripping surfaces have specially hardened teeth to 61HRC for positive grip on pipes and nuts. Plastic coated handles with slip guards for extra safety. Has 'no - nip' feature which prevents handles locking together and damaging users' hands. Display packed. Manufactured to DIN ISO 8976 Specifications