14Pcs Countersink Drill Bit Wood Plug Cutter Woodworking Screw Holes ToolFeature:* Made of high carbon steel + titanium plated high speed steel, which has excellent cutting force and durability, sharp and solid.* The countersink drill bit has an automatic starting point, which has 5-flute to eliminate chatter and vibration for stable operation, it has clean, accurate and burr-free cuts.* The standard 1/4" hex handle allows for quick changes, and the depth of the secondary socket can be adjusted with a grub screw head Allen wrench or a deeper cover to cover a matching stopper.* You can drill and counterbore the nut at the same time and keep both on the same axis. After the screw is tightened, the nut sits below the plane of the board.* The package includ.