Descriptions:Thread tap adopts spiral point and straight flute design, with clear threads and no burrs. Screw tap provides downward chip removal, fast and precise tapping, suitable for through-hole threads. Twist drill bit adopts a spiral flute chip space design to remove chips quickly and cleanly. Cutting edges provide neat and smooth cuts. Use an appropriate lubricant (such as cutting fluid or oil) to reduce friction and heat build-up. 6542 (M2) high speed steel tap & drill bit set offers high hardness and excellent wear resistance for durability and longevity, and good cutting performance for clean, precise holes. Titanium coated drill and tap sets offer enhanced hardness, corrosion and rust resistance, heat resistance, and reduced friction for smoother, faster drilling and tapping. Tap and drill bit set is widely for cast iron, aluminum, stainless steel, carbon steel, aluminum alloy, bronze and hard plastics. Use with tapping oil to get higher quality threads and more durable taps. Machine tap is used on drill presses, tapping/CNC/milling machines. Not recommended for hand use and electric drill tapping. Tips: Drill holes with a twist drill bit first, then tap with a thread tap. The cutting angle should be 90 degrees vertical and stable. The higher the hardness, the slower the speed. Tapping depth should not exceed 1.5 times the diameter of tap.