Features:  -[Wide application]: Suitable for workpieces with hardness less than 65HRC, such as stainless steel, aluminum plate, carbon steel, thin iron plate, insulating plate, PVC plate, wood board, etc;  -[Efficiency]: It has a one-piece design, which makes the chips generated during the chamfering process more convenient, and will not delay work efficiency due to tool blockage;  -[Grinding function]: The blade can be ground, and a more convenient maintenance method allows the tool to be ground without unloading;  -[Ease of use]: The automatic through-hole chamfering knife can quickly trim and chamfer both sides of the hole in a few seconds;  -[High-speed steel]: Excellent material, capable of processing various hard metals, and improved blades double the tool life.     Specifications:  Product Name: Countersunk Head Drill;  Size: 6.3/8.3/10.4/12.4/16.5/20.5mm countersunk drill +3mm twist drill;  Twist drill length: 61mm;  Color: Gold + charcoal black;  Material: HSS 6542 M6;  Hardness: 60°;  Design: Straight shank 90° 3 blade, oil-coated protective oil on the surface to prevent rust;  Quantity:  6x Countersunk drill;  1x Twist drill;  Package Included:  6× Countersunk drill;  1× Twist drill