Premium Material: Diameter: 5 inch / 125 mm. The 4-jaw mini lathe chuck body is made of cast iron that has passed rigorous quality tests. It has high strength and toughness, compression resistance and durability, and long service life. Reversible Jaw Set: The lathe chuck is equipped with 3 inward stepped jaws that can be stepped inward or outward to hold raw materials of different shapes. The high precision design of the chuck bevel gear guarantees the accuracy of the chuck operation. Enhanced Flexibility: The T shape chuck key of the lathe part allows the installation of various workpieces. And effortless operation reduces changeover time for your convenience. Internal Jaw Clamping Range: 0.276'-2.244' / 7-57 mm. External Jaw Clamping Range: 1.89'-4.92' / 48-125 mm. High Precision: The 4-jaw lathe chuck works accurately, bearing tolerance is of 0.003 inch / 0.07 mm to ensure satisfying metal processing