Three groups of edge, each in cutting process is responsible only for 1/3 of the workload, and inside each also has a cutting edge, also due , respectively, the burden of the characteristics of part of the cutting work, making the drill hole is not easy to produce the phenomenon of collapse. It’s easy to use with . The precise design will ensure its practicability in the work of high performance. Perfect and practical tool for metal hole cut. Features - Color: Silver. - Material: Hard alloy. - Outside diameter Size: 16mm, 18mm, 20mm, 22mm, 25mm,26mm,28mm, 30mm, 35mm, 40mm,45mm, 50mm, 53mm. - Positioning accuracy withnot shift. - Appliacation: Can be used for bench drill, electric drill chuck with the use of machine tools. - Suitable for the stainless steel plate, steel, casting, aluminum alloy, iron, metal plate, iron plate and other kinds of metal plate drilling. - Chip removal, with excellent performance, edge, wear-resistant. - Excellent cutting ability and very stable and accurate. Package list: 1 x 13Pcs Carbide Tip Drill Bit Hole Set Stainless Steel Metal Alloy 16-53mm