Versatile Collection: the ER11 spring collet set is truly a complete package; The set includes a total of 19 pieces, which comprise 15 different ER11 precision spring collets that range from 1mm to 7mm, 1/4Inch, and 1/8Inch sizes, along with 4 ER11A clamping nuts that have M14 threading; This diverse collection is specifically designed to cater to your requirements related to CNC carving milling machine chucks Broad Clamping Range: equipped with ER11 collets of varying sizes, you will receive a diverse clamping range with this set; 15 diameters include 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 1/4Inch, 1/8Inch; This ER11 precision spring collet set for CNC engraving offers you the flexibility to deal with a wide array of tasks seamlessly Reliable Quality: crafted from 65 Mn spring steel, the collets in this set are dependable tools promoting high precision, elasticity, and a secure grip; The ER11 spring collet nut set provides a smooth and stable cutting experience ensuring productivity as well as efficiency in your work High Precision: the ER11 collet chuck for CNC boasts of an accuracy level of 0.02 mm (0.0008 inches); This of precision is suitable for operations such as milling, drilling, tapping, and other relevant tasks, ensuring quality results every time Wide Applications: this spring collet set and nut set is perfect for a plethora of devices, like CNC, milling machines, engraving machines, and machining centers; The hex nut can be applied in conjunction with ER type knife handles, reamers, knife rods, extended rod nuts, fixed drills, and other tools, highlighting the set's versatility and adaptability Please note:the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour:As Shown Material:Metal Package Contents: 1 * ER11 precision spring collet set Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.