Adjustable Drilling Length: can be adjusted for different screw lengths simply by loosening and tightening the set screw. Multi-size: one tool for multiple uses, our 5 types taper drill bit set Sizes: 2.8x8mm/3.0x8mm/3.2x8mm/3.5x8mm/4x8mm to meet your needs. Material of Superior Quality: Made of high quality alloy steel. It is very suitable for wood hole drilling of various sizes. A versatile tool, improves work efficiency. Usage: Compatible with drills with chuck, for drilling on wood or parquet, for DIY, home and general construction or building use. engineering, etc. Efficiency: The spiral flute with a center drill will quickly discharge chips from the hole, the five-edge chamfer design effectively prevents debris accumulation and improves drilling efficiency Countertop Drill Bit Set 5-Piece Countersink Drill Bit Set, HSS for Woodworking, Plastic, Drilling Holes Removable and AdjustableDurable The countersunk drills are made of high quality alloy steel. High hardness and wear resistance, provides superior cutting performance, suitable for use with different sized wood holes Wide Uses:Adjustable and Removable Sets of wood drill bits come with a key to remove the screw and adjust the length of the countersunk hole to adjust the drilling length of screws of different lengths Spiral groove with a center drill discharges quickly the chips from the hole. The pentagonal design of the chamfer effectively prevents dirt build-up and improves drilling efficiency Countersunk drill bit setWide uses: The countersunk head is compatible with drills with chucks, for drilling on wood or wooden floors. It can be used for wood, plastic, soft metal, fiberboard, countersinks, holes, etc.