Features: Brass 4485 collet in 10 sizes for your choice: 0.5mm, 0.8mm, 1.0mm, 1.2mm, 1.5mm, 1.8mm, 2.0mm, 2.4mm, 3.0mm, 3.2mm. 1 metal replacement collet nut and 1 wrench. With brass collet and full metal nut, they are of better quality, more durable, and effectively prolong the service life. The replacement of the brass chuck greatly improves the accuracy and can fix the tiny drill bit more safely. Under high-speed rotation, the tool is better aligned, maintaining stability and improving work efficiency. This material is soft and easy to wear and tear, so we use a better quality brass material. For plastic nuts, they will break during use, and the all-metal material solves this quality problem very well. This replacement brass collet provides a big improvement in precision and holds these tiny bits far more securely and in better alignment with the rotation of the tool, under high-speed rotation, it not only maintains stability but also improves work efficiency. Specifications: Material:Brass Nut: 7x17mm Collet size: 0.5/1/1.2/2.4/3/3.2mm Nut: 8x17mm Collet size: 0.5/1/1.2/2.4/3/3.2mm Package Includes: 1 Set Collet note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.