High Hardness and Rust Resistance: These hex head taps are made of high speed steel and feature a nitriding surface finish for high hardness and rust resistance. Designed with spiral flutes: Taps with drilling function, used for drilling a hole and cutting new threads at the same time, will let you get a smooth tapping experience in metal, aluminum plate, iron, etc. More precise and efficient: Automatic centering point, does not require auxiliary center drilling and center punching, more accurate, eliminate human error, greatly reduce processing steps and time costs, improve work efficiency Anti-wear: The back of the cone is covered by the tap to prevent excessive punctures caused by damaged threads. 6 different sizes from M4 to M8: Quick change 6.35mm (1/4) hex shank with imperial sizes engraved on the taps to meet your various requirements Full specs A variety of specifications to choose from, convenient for work Tapping and drilling together Drilling and tapping are solved in one step, saving time and effort, all in one go HSS Material Dramatically improves wear resistance and cutting performance Spiral groove design Cut quickly and improve work efficiency Standard 1/4 hex handle Hexagonal handle design, stable clamping and quick replacement