8" Self-centering Welding Positioner Table Chuck Chuck Diameter: 200 mm (7.8")Center Hole Diameter: 80 mm (3.1")Clamping Range: front PAWS 20-130mm, back PAWS 110-210mmExtended clamping range: 5-300mm 12" Self-centering Welding Positioner Table Chuck Chuck Diameter: 300 mm (11.8")Center Hole Diameter: 100 mm (3.9")Clamping Range: 80-280 mm Self centering welding table chuck is made of excellent steel,which is wear-resistant and not easy to corrosion. Compact claw,high precision,heat is not easy to die,fast clamping speed,easy operation,high welding and cutting efficiency. The thinner chuck reduces the center distance of the workpiece and increases the carrying capacity of the welding equipment. Chuck is suitable for all kinds of lathe, grinder,milling machine,drilling machine and machine tool accessories. 8inch and 12inch 3 JawsSelf-centering Welding Positioner Table Chuck Reversible claw can be used as internal claw or external claw, chuck is suitable for all kinds of lathe, grinder,milling machine,drilling machine and machine tool accessories.