High Quality: Forstner Drill Bit made of Tungsten carbide with special heat treatment for sharp cutting edge, high hardness, non-burrs and durable use. Cutting Diameter: 3-3/8 Inch / 85mm, Total Length: 3.15 Inch / 80mm, Round Shank Diameter: 0.39 Inch / 10mm. Design: Small incision resistance, improve the opening speed. It's head adopt arc curve design, beneficial to chip removal, perforation is more efficient. Clean & Accurate Cutting: Two spurs and centering point can offer repeated, clean and accurate cutting holes. The sharp center spur accurately locates the center of your hole. Application: Can be used for drilling holes on wood and plastic products, furniture, door hinge. Used on cutting wood, plywood, solid wood boards, MDF, plastics, fiberglass etc.. Suitable for bench drill, vertical drilling machine, hand held electric drill, impact drill, CNC carving machine and other drill press. Purchase Guarantee: Please rest assured to buy our product. If you are not satisfied with the product, we provide a 100% money back guarantee within 90 days