1. The chuck has large clamping force, which can be tightened quickly and operated stably. 2. The hole diameter and thread have high precision, standard size, and it is not easy to fall off after installation. 3. The 122mm lengthened design is convenient for tool installation and removal. 4. Made of high quality and high hardness materials, shockproof and wear resistant, and can be used for a long time. 5. Different size specifications have different clamping ranges, which is more practical. Specifications: Item Type: Grinding Chuck Model: 10-16mm Grinding Machine Chuck Hardness: HRC40-45 Clamping Accuracy: 0.02mm Clamping Range: Approx. 10mm/0.39in, 11mm/0.43in, 12mm/0.47in, 13mm/0.51in, 14mm/0.55in, 15mm/0.59in, 16mm /0.63 inch Pliers Total Length: Approx. 122mm / 4.8in Diameter of Plier End: Approx. 20mm / 0.8in Tail Thread: M20 Tail Thread Length: Approx. 29mm / 1.1in Shank Diameter: Approx. 20mm / 0.8in Package List: 1 x 12mm Chuck Note: 1. Place each type of chuck into the corresponding diameter tool to avoid damage to the chuck because the tool diameter exceeds the model size of chuck. 2. When changing tools, clean the impurities inside the jacket in time to ensure the life of the chuck.