Drill tap bits increase efficiency of operation by allowing for drilling and tapping to be accomplished in a single pass. These HSS drill and tap bits are great tools used to create screw threads, to cut or form the female portion of the mating pair. They are used on a machine to do the tapping, such as a lathe. Features: High hardness, rustproof, solid and durable. There are total 12pcs of taps in 2 different standards that you can use for tapping various threads. Drilling and tapping at the same time, save you time and effort. Taps are designed with spiral flutes and the chip clearing process would be better. Their specifications are marke d clearly on the surface, convenient to choose. Specification: Material: High Speed Steel (Titanium Coated) Standard: Metric, Inch Color: Metric: Gold, Inch: Silver Hex Shank: 6.35mm(1/4") Metric Size: M3*0.5mm, M4*0.7mm, M5*0.8mm, M6*1mm, M8*1.25mm, M10*1.5mm Inch Size: 1/4-20NC,12-24NC,10-24NC,10-32NC,8-32NC,6-32NC Quantity: 12pcs Weight: Approx. 192g Package List: 12 x Thread Tap 1 x Red Case