Multiple Sizes: This set includes 4pcs countersink drill bits and 4pcs claw drill bits to meet your daily working needs. Each shape has four sizes, 1/4", 3/8", 1/2", 5/8" (6mm / 10mm / 13mm / 16mm). Shank Diameter: Approx. 9.5mm. High-quality carbon steel: The wood plug cutter set is made of carbon steel, durable and corrosion-resistant, high precision, high strength and smooth surface. Practical functions: 4-tooth chamfer punches make tapered plugs to fill countersinks, while standard punches are used to remove wood defects. Wide applications: Suitable for bench drills and hand drills, we recommend using bench drills for more stable operation and improved work efficiency. Note: The speed should not be too fast, as it is easy to produce smoke, burns, etc.