These taps are made of high speed steel and their surface is finished by nitriding for high hardness and rust resistance There are total 6 pieces of taps in different sizes from M3 M10 that you can use to tap various threads The taps are designed with spiral flutes and the chip cleaning process would be better These are taps with drilling function, used to drill a hole and cut new threads at the same time, you will have a smooth tapping experience with them These taps are used on a machine to do tapping, usually more accurate as human error is eliminated Specifications: 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 Pitch: 0.5 mm, 0.7 mm, 0.8 mm, 1.0 mm, 1.25 mm, 1.5 mm Used on: Machine Function: drilling Quantity: 6 Package includes: 6 x taps