Uxcell M5 X 0.8 Spiral Point Thread Tap And 4.2Mm Drill Bit Set, Metric Titanium Tap and Drill Bit: Tap thread size: M5 x 0.8, drill bit diameter: 4.2mm / 0.17". High-speed steel tool has high hardness and toughness for wear resistance. Good for general purpose applications. Spiral Point Tap: Spiral point design, downward chip removal, right hand thread cutting. Suitable for processing through-hole threads, and tapping aluminum, stainless steel, bronze, hard plastics. Titanium coating provides excellent corrosion resistance and wear resistance. Twist Drill Bit: Spiral chip space design for fast and clean chip removal. Sharp cutting edge provides smooth cutting and no glitches. Cobalt high speed steel tool features high hardness (HRC65-66) and high red hardness, high wear resistance Usage of Tap: Used on 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 of Drill Bit: Suitable lubricant is conducive to cutting or cooling, making cutting easier, improving smoothness and dimensional accuracy. Select an appropriate feed rate and cutting speed to improve the tool life.