Shank Type: Taper Shank Taper Size: CAT50 Hole Diameter (Inch): 3/8 Nose Diameter (Inch): 1 Projection (Decimal Inch): 4.5000 Through Coolant: Coolant Through Clamping Depth (Decimal Inch): 3.0000 TIR (Decimal Inch): 0.0002 Coolant Type: Through-Spindle Retention Knob Thread Size: 1-8