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 J G L2Ref L1Ref LRef Designation Range L L1 L2 D D1 G J BT30 ER16X70* 0.5-10 70 48 28 M12 M10 BT30 ER16X100* 0.5-10 100 73 28 M12 M10 BT30 ER20X70* 1-13 70 48 34 M12 M12 BT40 ER16X70 0.5-10 70 43 28 M16 M12 BT40 ER16X100 0.5-10 100 73 28 M16 M12 BT40 ER16X150 0.5-10 150 123 110 28 40 M16 M12 BT40 ER16X200 0.5-10 200 173 85 28 40 M16 M10 BT40 ER20X70 1-13 70 43 34 M16 M12 BT40 ER20X100 1-13 100 73 34 M16 M12 BT40 ER20X120 1-13 120 93 34 M16 M12 BT40 ER20X150 1-13 150 123 34 M16 M12 BT50 ER16X100* 0.5-10 100 62 28 M24 M12 BT50 ER16X125* 0.5-10 125 87 28 M24 M12 BT50 ER16X150* 0.5-10 150 112 28 M24 M12 BT50 ER16X200* 0.5-10 200 162 85 28 40 M24 M10 BT50 ER20X100* 1-13 100 62 34 M24 M12 BT50 ER20X125* 1-13 125 87 34 M24 M12 BT50 ER20X150* 1-13 150 112 34 M24 M12 BT50 ER20X200* 1-13 200 162 85 34 50 M24 M12 Add B for coolant through the flange. * Balanced to G6.3 at 12,000RPM 801