Feature●Stable and durable: these collets are stable and durable due to their high quality spring steel.●Range: 3 mm, 1/8 inch, 4 mm, 5 mm, 6 mm, 1/4 inch, 8 mm, 10 mm, 12 mm, 1/2 inch.●Practical and portable: each collet is packed in a separate protective container with label for you to use it conveniently.●NOTE: The collet must be inserted into the collet nut before inserting into the collet chuck.Description