4-Jaw, Direct Mounting "D" Series Independent Lathe Chuck The reversible jaws and operating screws are made of high quality carbon steel, the jaws are precision ground. Independent chucks are designed with jaws that move independently of one another. Cast iron also called semi-steel is the industry standard for chuck body material. Features include... 8" Chuck Diameter 2.16" Thru Hole To fit Spindle: D1-5 1 Set of 4 Jaws 1 Set of Mounting Screws 1 Hexagon Wrench