2MT (M10 & 3/8"whitworth drawbar) Arbor's Mounting Thread - M14 x 1, Arbor's Shank - MT2 / 2MT / Morse Taper 2. 3MT (Arbor's Drawbar - M12 x 1.75), Arbor's Mounting Thread - M14 x 1, Arbor's Shank - MT3 / 3MT / Morse Taper 3.
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