Material: high speed steel (HSS), suitable for soft metals, aluminum, iron Metric: M3x0.5, M4x0.7, M5x0.8, M6x1, M8x1.25, M10x1.5 More accurate and efficient, self-centering point, does not require auxiliary center drilling and center punching, more accurate, eliminate human error, greatly save processing steps and time costs, improve work efficiency. Anti-wear,The back of the cone by the tap to prevent excessive punctures caused by damaged threads.