Milling Chuck Taper Size HSK63A Hole Dia 3/4 in Nose Dia 1.8900 in Collet Series KM3/4 Projection 95.00mm Coolant Fed Coolant Through Bore Depth 2.0800 in to 3.1500 in Clamping Range 1/8 in to 3/4 in Features 140 Percent More Bearing Surface than Competitor Milling Chucks For Quiet and Stable Heavy Milling Nikken Patented Design Nut Body Contact Nose Clamping and Anti-Vibration Mechanism Thick Body and Internal Slots Provide Extremely Strong Chucking Torque and Rigidity