Features: High quality: 6PCS 1/4 hexagonal 5-slot 90-degree countersunk drill bits made of standard high-speed steel. High speed steel countersunk bit has high toughness and hardness after high-frequency quenching treatments. Chamfering cutting coated with titaniums, rust prevention, long service life. 7PCS three-tip countersunk bit made of high quality carbon steel: Good wear resistance and durability, including 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 10mm0.12, 0.16, 0.2, 0.24, 0.28, 0.31, 0.39 for drilling pilots holes, large chip grooves and five side chamfer for rapid sawdust, It39;s easier to expel. The 8PCS corkcutting drill set is made of durable carbon steel material: for tapering 1/4 , 3/8 , 1/2 , 5/8 corks to cover dented screw holes or hided-blemishes. It can be used with benches drill, hand drill or other professional benches drill. To avoid skidding or eccentricity, we recommend using benches drill, or a fixed bit. Included in the package: A total of 23 pieces of woodworking chamfer drill tools. 6 x 1/4 hex countersunk bit, 7 x 3/8 round shank countersunk bit, 1 x L wrench. 1x automatic center press. Application objects: Suitable for wood, fiberboard, particleboard, plywood, plastic, aluminum alloy board, PCB board, etc. We offer different corking bits. You can use it in any hole you need. Notice: 1.Actual color may be slightly different from the image due to different light effect 2.Please allow 1-3cm deviation due to manual measurement Description: Material:Carbon Steel Size:As Picture Shown Package List: 23 Pcs*Five-edge Corkscrew Drills