Standard 1/4'' hex shank countersink drill bit for convenient to quick change, improve your work efficiency Made of high-quality carbon steel with high-frequency quenching treatment, high hardness and strength, wear resistance Countersink Chamfer Drill Bit Set with 3 Different Size: 12mm, 16mm, 19mm, great for wood openings, reaming, chamfering, screw head, etc. 5 Flute 90 degree chamfering for sharp and accurate countersinking drilling holes, great for wooden planks, fiberboard, particleboard, plywood, plastic, aluminum board, etc. Please Note: Not suitable for high-hardness metal material such as steel and iron. Specifications: color: as show Material: High-Quality Carbon Steel Angle: 90 Degree Shank:1/4" (6.35mm) Hex Shank Countersink Diameter: 12mm/ 16mm/ 19mm Package Includes: 1 * Countersink Drill Bit (12mm) 1 * Countersink Drill Bits (16mm) 1 * Countersink Drill Bits (19mm)