Description: All working parts precision ground and hardened Completely sealed for maintenance free operation! Turning: The unequaled rigidity of this toolpost and holders insure smoother turning without chatter or vibration! Drilling: Set enables you to drill feed with your carriage instead of hand operation or tailstock SHB 20- 3 Φ3mm for Small bore inner hole turning tool holder Specification: Outer diameter: 20mm/0.78inch inner hole diameter: 3 mm/0.12inch Package Includes: 1 Piece Carbide Boring Bar