【6 Pack】: 6pcs chamfer cutters are available in six different diameters of 6.3mm/8.3mm/10.4mm/12.4mm/16.5mm/20.5mm. Different diameters can be used for drilling. 【Sharp Anti-Rust】This cutter is made of HSS high speed steel, high hardness and not easy to rust. Its cutting edge is hardened and ground, so it is sharper and has a longer service life. ✔Note: When using a countersink bit on a hand drill, drill the hole with a twist drill and then use a countersink bit to avoid any risk of sloshing caused by drilling. 【More Machining Materials】: 6pcs walnut countersink bits can chamfer the edges of holes. Conical countersinks can process various materials such as hard wood and cork, aluminum foil, plastic, etc. PVC and light iron. This chamfer cutter is suitable for all kinds of machine tools. 【Chamfer design】: The chamfer cutter has the corresponding inclination angle design, rust-proof and corrosion-resistant, beautiful and delicate, giving it the strength and rigidity of the sharp-edged