CA#400 Quick Change Tool Post 6 PCS Set, CNC Lathe Piston Type, For Lathe Swing 14″-20″. The locking mechanism of piston tool post is to push the holder out against the angle gib ways of dovetail by the center hole piston Precision ground and hardened on the piston contact surface and the dovetail to ensure rigidity and repetitive accuracy Advanced design provides built in quick tool changing versatility with positive rigidity to meet the most exacting working tolerances Quickly and easily installed on an engine, bench or turret lathe for a wide range of operations, from fine precise work to heavy duty cutting CA Piston Type Set Included one of each: Quick Change Tool Post; No. 1 Turning & Tool Holder with 1/4-5/8 Tool Capacity; No. 2 Boring, Turning & Facing Tool Holder with 1/4-5/8 Tool Capacity; No. 4 Boring Bar Tool Holder with 3/4 & 1 capacity; No. 7 Universal Parting Blade Tool Holder with 11/16 blade height; No. 10 Knurling, Facing & Turning Tool Holder 1/4-5/8. Precision ground and hardened on the piston contact surface and the dovetail to ensure rigidity and repetitive accuracy. Advanced design provides built in quick tool changing versatility with positive rigidity to meet the most exacting working tolerances. Quickly and easily installed on an engine, bench or turret lathe for a wide range of operations, from fine precise work to heavy duty cutting. The locking mechanism of piston tool post is to push the holder out against the angle gib ways of dovetail by the center hole piston. CA Piston Type Set Included one of each: Quick Change Tool Post; No. Date First Available: March 9, 2022. And we will work with you to resolve it to your satisfaction.