Includes 1 collet chuck,1 clamping nut, & set of 10 ER25 collets and 1 spanner Collet Sizes - 3,4,5,6,8,10,12,14,15,16 mm Collet chuck tapped M12 for a drawbar Packed in a plastic case High precision collet chuck system suitable for all milling and drilling applications. Wide holding range. Accuracy:0.015mm