High Efficiency: This tapping drill improves working efficiency by enabling both drilling and tapping. Main function: This tap drill ideal for making threads, cutting or forming a concave part of a mating pair. High Quality: This drill bit is made of high speed steel and has a nitride surface for high hardness and rust resistance. M3 - M10: This tapping bit has 6 different sizes, 6 different sizes of taps from M3 to M10 which can be used to connect a variety of threads. High precision: This tapping bit uses a spiral groove design which facilitates the chip cleaning process. These tapping bits for tapping, which is generally more accurate as it eliminates human error. Features Material: High Speed Steel (Titanium Coated) Color: As Pictures Show Hex Shank: 6.35mm (1/4") Standard: Metric Thread: M3, M4, M5, M6, M8, M10 Distance: 0.5mm, 0.7mm, 0.8mm, 1.0mm, 1.25mm, 1.5mm Used on: machine Function: drilling Quantity: 6 Note: The data is all manual measurement, please allow 1 - 3cm error,