Item Type: Collet Replacement_x000D_ Model: 1/2, 1/4, 1/8in Grinding Machine Chuck_x000D_ Hardness: HRC40-45_x000D_ Clamping Accuracy: 0.02mm_x000D_ Clamping Range: Approx. 3.175mm / 0.1in, 6.35mm / 0.3in, 12.75mm / 0.5in_x000D_ Collet Total Length: Approx. 122mm / 4.8in_x000D_ Collet End Diameter: Approx. 20mm / 0.8in_x000D_ Tail Thread: M20_x000D_ Tail Thread Length: Approx. 29mm / 1.1in_x000D_ Rod Diameter: Approx. 20mm / 0.8in 1Mount the chuck on the tool of the corresponding diameter, which can be well matched with the hand tool. 2The clamping force is strong, and the clamping accuracy is 0.02mm, which is suitable for fine operation. 3Made of high-quality materials, the hardness is HRC40-45, which is not easy to squeeze and wear. 4The collet size is standard, the thread is accurate, and it is not easy to fall off after installation. 5The collet is integrally formed with a long total length and is suitable for installation on a knife sharpener.1. Put each type of chuck into the corresponding diameter tool to avoid damage to the chuck because the diameter of the tool exceeds the size of the chuck model._x000D_ 2. When changing tools, clean up the impurities inside the jacket in time to ensure the service life of the chuck.1 x 1/2-12.75mmCollet