6 pieces: 6 There six different diameters are available for the 6.3mm / 8.3mm / 10.4mm / 12.4mm / 16.5mm / 20.5mm countersinks Different diameters are available for the holes.< /p> Sharp and Rustproof The knife is made of HSS high speed steel, which has high hardness and is not easy to rust. Its cutting edges are hardened and ground so they are sharper and last longer. NOTICED : If you use a drill Use the countersunk drill on the electric drill, drill the hole with a twist drill, and then use the countersunk drill to avoid the risk of shaking caused by drilling. More processing materials: 6 walnut countersunk holes can chamfer the edge of the hole and can process different materials such as hardwood, softwood, foil, plastic, PVC, iron lamp, etc. The chamfering knife is suitable for various machine tools Chamfering design: the chamfering tool adopts an appropriate tilt design, which is rust-proof and anti-corrosion, beautiful and delicate, makes the tool sharp strength and rigidity, and greatly increases Machining performance of cutters, cutting and milling. Scope of application: This countersunk head drill kit is suitable for home DIY and daily use, it can drill holes easily and efficiently, not only without burrs, but also without scratches. > This countersunk drill bit is made of high quality high speed steel, which has high hardness and is not easy to rust. For example, it can be processed on steel sheets, wooden boards and plastic boards The countersunk drill bit has six diameters: 20.5mm, 16.5mm, 12.4mm, 10.4mm, 8.3mm and 6.3mm. A variety of sizes to meet your drilling needs Twist Drill Equipped with a twist drill bit for positioning, you can use HSS tools more efficiently and with more Precision 6 x Deburring Knives: 20.5mm, 16.5mm, 12.4mm, 10.4mm, 8.3mm and 6.3mm Note: The data is all measured manually, please allow 1-3 error cm, due to the difference in light and display, there will be a certain color difference, the actual object received shall prevail.Note: The data is all manually measured, please allow 1-3cm error, depending Due to the light and display difference, there will be a certain color difference, the actual object received shall prevail.