Description: This is a collet chuck assembly that forms a collar around an object to be held and exerts a strong clamping force on the object when tightened. The clamp can be compressed so that its interior surface contracts to a slightly smaller diameter, gripping the tool whose secure hold is desired. Features: This collet chuck set contains 1 black cap and 6 different sized sleeves for various holding needs. The black cap is made of carbon steel and the sleeve is made of high quality brass for durability and good performance. This collet chuck set allows for quick tightening, simply loosen one part, move to a new part and close again. The collet chuck ensures strong clamping force and holds securely while working under correct conditions. The black cap can be easily tightened by hand with the exclusive non-slip design. Specifications: Material: Brass, carbon steel Color: as pictures show Black cap size: M8 x 0.75mm Clamp sleeves size: 1mm, 1.6mm, 2mm, 2, 4mm, 3.2mm, 3mm Package includes: 6 x Clamp Sleeves 1 x Cap