BT - ER COLLET CHUCK - METRIC Taper SizeBT 30, 40 and 50 A ➚ A .003 AT3 Taper 58-60 HRc N5 G2.5 D1 20,000 RPM D G J L2Ref L1Ref LRef Designation Range L L1 L2 D D1 G J BT30 ER25X 60* 1-16 60 38 42 M12 M16 BT30 ER32X 60* 2-20 60 38 50 M12 M16 BT40 ER25X 60 1-16 60 33 42 M16 M16 BT40 ER25X100 1-16 100 73 42 M16 M16 BT40 ER25X150 1-16 150 123 42 M16 M16 BT40 ER32X 60 2-20 60 33 50 M16 M22x1.5 BT40 ER32X100 2-20 100 73 50 M16 M22x1.5 BT40 ER32X120 2-20 120 93 50 M16 M22x1.5 BT40 ER32X150 2-20 150 123 50 M16 M22x1.5 BT40 ER32X200 2-20 200 173 50 M16 M22x1.5 BT40 ER40X 80 3-26 80 53 63 M16 M28x1.5 BT40 ER40X100 3-26 100 73 63 M16 M28x1.5 BT40 ER40X150 3-26 150 123 63 M16 M28x1.5 BT40 ER40X200 3-26 200 173 63 M16 M28x1.5 BT40 ER50X 90 10-34 90 63 78 M16 M28x1.5 BT50 ER25X100* 1-16 100 62 42 M24 M16 BT50 ER25X150* 1-16 150 112 42 M24 M16 BT50 ER25X200* 1-16 200 162 87 42 55 M24 M16 BT50 ER32X100* 2-20 100 62 50 M24 M22x1.5 BT50 ER32X125* 2-20 125 87 50 M24 M22x1.5 BT50 ER32X150* 2-20 150 112 50 M24 M22x1.5 BT50 ER32X200* 2-20 200 162 88 50 63 M24 M22x1.5 BT50 ER40X100* 3-26 100 62 63 M24 M28x1.5 BT50 ER40X150* 3-26 150 112 63 M24 M28x1.5 BT50 ER40X200* 3-26 200 162 63 M24 M28x1.5 BT50 ER50X100* 10-34 100 62 78 M24 M36x1.5 BT50 ER50X150* 10-34 150 112 78 M24 M36x1.5 Add B for coolant through the flange. * Balanced to G6.3 at 12,000 RPM 802