In addition to providing excellent access between the chuck body and the rear of the workpiece, these Jaws are highly practical when working with pre-turned or long workpieces that require refastening. Whether you're turning serviette rings or remounting rough-turned work, these Jaws can make the process much more efficient.
The sizes indicated on the drawing represent the Jaws when they form a perfect circle. When used with the VM90 or VM100 chucks, you can expect approximately 38mm of expansion beyond these specified sizes.