Self-centering Wood Chuck Set for 3.75 Inch Steel 147834This wood chuck set for 95 mm (3. 75 inches) is a mechanical device used to clamp a workpiece on a machine tool. Made of steel, the set is durable and sturdy. As a machine tool accessory, it uses the radial movement of movable jaws evenly distributed on the chuck to clamp and position the workpiece. This wood lathe chuck set includes a 4 jaw self centering chuck and interchangeable jaws for spindles, bowls, and work pieces that are hard to be secured.