1/32"- 5/8" Heavy Duty Drill Chuck with Chuck Key and MT3 Arbor THIS DRILL CHUCK HAS MT3 (THE SPINDLE HOLE DIA MUST BE 0.94") SHANK NOT MT2 Chuck Overall Length: 3.66" Clamping Range: 1/32" - 5/8". Accuracy: 0.005" Shank: MT3 (Morse Taper 3)