Tested to 10, 000V & insulated to 1000V AC & 1500V DC for live line working. Manufactured from chrome vanadium electric steel, oil hardened & tempered with smoothly ground chrome plated jaws with joint faces & an accurately formed box joint. Nine position adjustment, with 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