(Jack) Kuhn of South Gate, California. This is a KDK 400 Series Quick-Change Tool Post Holder. Fits 100, 150, 200, 400 KDK Tool Posts. 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. KDK-406: 4-Position Bar Combination – 1-1/4 Capacity. Comes exactly as shown in pictures.