Feature:1. Using straight shank integrated design, come with high accuracy and good rigidity2. Automatically tighten keyless device, automatically increase the clamping force, very practical3. Key parts of drill chuck is made after special quenching treatment to improve durability, useful and helpful4. Excellent 40Cr material have high tensile strength, yield strength and hardenability, come with high fatigue strength and good toughness5. The hardness is 40HB, clamping range from 1‑16mm, and the applicable machine tool is a milling machine, very usefulSpecification:Item Type: Integral Drill ChuckMaterial: 40CrAccuracy: 0.08mmHardness: 40HBClamping Range: Approx. 1 ~ 16mm / 0.04 ~ 0.63inApplicable Machine Tool: Drilling machine Package List:1 x Integral Drill Chuck