3/16"- 3/4" Heavy Duty Drill Chuck with 2MT Arbor In Prime Quality Clamping Range: 3/16" - 3/4". (PLEASE NOTE THE DRAWS DO NOT CLOSE ENTIRELY TO ZERO RATHER IT CLOSE TO 3/16") Chuck Overall Length: 4.33" Shank Diameter: 2.57"; Shank Size: 2MT (Morse Taper #2) PLEASE NOTE THE TAPER IS MT2 (SPINDLE HOLE DIA OF DRILL PRESS SHALL BE 0.70'. ) Accuracy: 0.005" JT3 Mounted