Features: High hardness manganese steel, long hardness life, not easy to corrosion., solid and durable to use. Good metal texture, comfortable surface, easy to clamp, so that the output torsion becomes larger. Keyless design, tightening and loosening is by hand force, which offers a quicker and easier chucking and unchucking. Beautiful and practical design of the surface convex and concave, so that before and after the set can effectively cope with and can reduce the shaking jacket. Widely used with various drill machines, milling machines, lathes, boring lathes and electric hand tools. Specifications: Condition:100% Brand New Material: Manganese steel Color: As shown in the picture Connecting Rod: Taper Mohs No. 3 Maximum Diameter: Approx. 23.825mm/0.9in Short Head Size: Taper M18 Maximum Diameter: Approx. 17.78mm/0.7in Package List: 1*Self Tighten Drill Chuck