This is a KDK 00 Series Quick-Change Tool Post Holder. For lathes with up to 8 swing. Only a second to change tools. Rugged – No chatter or vibration. No time wasted with shims. Safe and simple to operate. Speed your lathe operations up to 90%. For fine precision work to heavy-duty cutting. BR100: Turning & Facing – 7/16 Capacity. Overall Dimensions: 1-3/4″ x 1″ x 2-1/4 high. Comes exactly as shown in pictures.