Straight Shank Drill Chuck Arbor Inch to Jacobs Taper. Precision ground, Made of high quality Steel, Used in Machining applications. Taper Mount and Taper Shank Shank to Taper Runout <0.0001". Through Coolant Capabilities.??HIGHEST ACCURACY: Precision Ground??HIGHEST TOLERANCE: Taper to Shank Runout < 0.0001"??Shank Taper: Straight (Inch)??Mount Taper: Jacobs Taper??HIGH QUALITY STEEL: Made of High Quality Hardened STEEL..Precisely Ground High Quality SteelChinaManufacturer100% Guarantee to be Free from any Manufacturing Defects. 100% Customer Satisfaction Guarantee