The countersunk heads have a titanium coating which makes them very strong. It chamfers really clean, no jerks, and a very smooth and regular chamfer, makes beautiful holes without splitting the plywood. These countersunk bits are very good for deburring holes made with a screwdriver or for being able to fully insert screws without them protruding. Easy to use, to attach to the drill chuck. We like to have for clean and neat work and it will especially prevent accidents because we can easily be injured by a screw that protrudes or is not properly inserted. This set of 6 reinforced and very hard countersinks are perfect for all jobs around the house. They hide screws in wood. The drill bits are made of HSS and are respectively sized: 6mm, 8mm, 9mm, 12mm, 16mm, 19mm. are perfect for drilling wood. 6Pcs Countersink Bits with 5 Flutes in HSS Countersink Drill Bit Hex Shank Set of 6 countersinks of different diameters that allow you to make chamfers on the edges of holes. This way the head of your screw is well protected. These countersinks are suitable for machining wood. Easy to use, attach to the drill chuck. Attention: Not applicable to stainless steel, cast steel, iron, copper, aluminum coatings, and carbon steel, thin iron plates Material: hard steel Package included: 6x Countersinks (6mm, 8mm, 9mm, 12mm, 16mm, 19mm)Welcome to meet