1. The 6-piece set of 3-blade 90 degree milled bits is suitable for processing metal and some non-metallic materials, such as carbon steel, steel, iron plate thin, insulating plate, PVC plate, aluminum, soft hardwood, plastic, etc. 2. Titanium-plated countersunk drills are very sharp, have high precision in circumferential machining and are durable. 3. Specifications: head diameter x handle diameter x 6.3mm length: 6.3mm x 5mm x 45mm. 8.3mm: 8.3mm x 6mm x 50mm. 10.4mm: 10.4mm x 6mm x 50mm. 12.4mm: 12.4mm x 8mm x 6.52mm 16.5mm x 10mm x 60mm. 20.5mm: 20.5mm x 10 mm x 65 mm. 4. The high quality countersunk drills can remove burrs well without leaving any scratches and are compatible with various ordinary drilling rigs including vertical drilling rigs. Model: HSS Chamfer Drill Set Size: Blue Iron Box Specifications: Model: HSS Chamfer Drill Set Type: Wood drill Material: 4341 high speed steel Surface treatment: Titanium coating Quantity: 6 pieces Features: This product can finish the treatment of conical surface at one time. Size: Head diameter x shank diameter x total length 6.3MM: 6.3MM x 5MM x 37MM 8.3MM: 8.3MM x 6MM x 40MM 10.4MM: 10.4MM x 6MM x 39MM 12.4MM: 12.4MM x 10MM x 46MM 16.5MM: 16.5MM x 10MM x 47MM 20.5MM: 20.5MM x 10MM x 47MM Advantages: 1. One-piece design: Debris generated during the chamfering process falls off more easily and will not delay work efficiency due to tool jamming 2. The blade can be rectified: a more practical means of maintenance, the tool can be rectified without unloading 3. A simple one-step process: The automatic through-hole chamfering cutter can quickly cut and chamfer both sides of the drilled hole in seconds 4. Excellent material: All kinds of soft or ferrous metals can be processed, and the improved cutting edge doubles the tool life. Packing list: Countersink drills 6 X 90 degrees