Material: High Speed Steel 4341,Made of high speed steel (HSS), high hardness and rust resistance for long service life.Size: M3x0.5, M4x0.7, M5x0.8, M6x1, M8x1.25, M10x1.5. 6 sizes set, which perfectly meet your different needs. A sharp, hardened drill bit induction, slightly induced wear-resistant, to ensure the puncture speed, improve work efficiency. Complete drilling, tapping, deburring and countersinking in one operation, save processing steps and time costs, improve work efficiency. 6 steel drill bits, suitable for drilling wood, plastic, thin copper, aluminum and other soft metals (5-6 mm), not for hard materials (e.g. steel sheet). When drilling a hole, you should inject water at the same time to cool the drill bit. This will help you increase the value of the drills. If you can't cool the drill bit when drilling holes, the drilling speed should not be too high and you should not drill too frequently.Color:SilverFeatures:Drilling, tapping and deburring/countersinking.Suitable