General description 1/4 Inch Hex Shank Countersink Drill Bit Set designed for woodworking, featuring 4 HSS drill bits suitable for screw sizes #6, #8, #10, and #12. This set allows you to drill and countersink for wood screws without the need to change drill bits, making it efficient and convenient for various projects. Technical specifications Drill bit sizes: #6, #8, #10, #12 Hex shank size: 6.35mm Material: HSS (High-Speed Steel) Suitable for workpieces with hardness below 25 HRC Compatibility and accessories Compatible with quick change drill chucks Includes 1 small hex key for adjusting countersink sleeve depth Installation Drilling length can be adjusted by loosening and tightening the set screw Usage Use on a drill with a chuck or connector Ideal for drilling into carbon steel, sheet metal, insulation board, PVC board, and wooden board