CAT - ER COLLET CHUCK Taper Size A ➚ A .00012 AT3 Taper 58-60 HRc Ra 4µin CAT-30, 40 and 50 L Ref L1 Ref G2.5 G D1 L2 RefJ 20,000 RPM D D D G JD1 L2Ref L1Ref ER16-20 LRef ER25-50 Designation Range L L1 L2 D D1 J G CAT30 ER16X2.750* .022-.396 2.750 2.000 1.370 1.102 1.248 M10 1/2-13 CAT40 ER16X2.750 .022-.396 2.750 2.000 1.370 1.102 1.752 M12 5/8-11 CAT40 ER16X3.937 .022-.396 3.937 3.187 2.560 1.102 1.752 M12 5/8-11 CAT40 ER16X5.906 .022-.396 5.906 5.156 3.350 1.102 1.752 M12 5/8-11 CAT40 ER20X3.937 .041-.514 3.937 3.187 2.560 1.339 1.752 M12 5/8-11 CAT40 ER20X4.000 .041-.514 4.000 3.250 2.620 1.339 1.752 M12 5/8-11 CAT40 ER20X5.906 .041-.514 5.906 5.156 3.780 1.339 1.752 M12 5/8-11 CAT50 ER16X3.937* .022-.396 3.937 3.187 2.560 1.102 2.752 M12 1-8 CAT50 ER16X5.906* .022-.396 5.906 5.156 3.490 1.102 2.752 M12 1-8 CAT50 ER16X8.000* .022-.396 8.000 7.250 2.980 1.102 2.752 M12 1-8 CAT50 ER20X3.937* .041-.514 3.937 3.187 2.560 1.349 2.752 M16 1-8 CAT50 ER20X5.906* .041-.514 5.906 5.156 4.530 1.349 2.752 M16 1-8 CAT50 ER20X8.000* .041-.514 8.000 7.250 4.620 1.339 2.752 M16 1-8 Add B for internal coolant flange. *Balance to G6.3 12000 RPM. 779