Thread Size: (SAE) 6-32NC 8-32NC 10-24NC 10-32NC 12-24NC 1/4-20NC, (Metric) M3 x 0.5 M4 x 0.7 M5 x 0.8 M6 x 1.0 M8 x 1.25 M10 x 1.5
Hex Shank Size: 1/4"

The 3-in-1 combination drill and tap bit set can complete hole drilling, tapping, and countersinking. Three processes in one, one-step operation, greatly saving processing steps, improving work efficiency, and providing accurate processing results. Tap drill bit set includes a quick-change adapter for easy bit changes.
Metric combination tap drill bit is used to create threaded holes, great for situations where both drilling and tapping are required. Can process both through holes and blind holes. Suitable for tapping aluminum, bronze, hard plastics, and other softer materials.
Self-centering point, do not need assistant center drilling or center punching. Quick change 1/4-inch hex shank can be used on power tools more easily and securely. A tapered end on hex shank can prevent excessive tapping. It exceeds the tap to prevent thread breakage from over-drilling.
HSS4341 thread taps offer standard hardness, good wear resistance and heat resistance for general purpose threading applications. Features the base substrate without any coatings, well suited for most general purpose tapping.
Works with drilling machines, tapping machines, CNC and milling machines. Use with tapping oil to get higher quality threads and more durable taps. Machine taps are suggested to be used with tap collets with overload protection.
Tips: Recommended feed rate: general steel: 6-15m/min; harder steel: 5-10m/min; stainless steel: 2-7m/min; cast iron: 8-10m/min. The torque caused by too fast feed speed is too large, which can easily cause the tap to break. Taps are prone to chipping or breaking due to speed overload or non-vertical tapping.