Description:1. Made of high-speed steel, with high hardness and stable operation. The drill bit is titanium-plated, which has higher wear resistance and lower friction coefficient. Not easy to accumulate chips and long service life.2. This twist drill is proper for electric drill, hand electric drill and impact electric drill. Suitable for DIY resin, amber, wood, plastic, soft metal drilling and carving.3. Spiral flute design for quick cleaning of chips. The sharp cutting edge provides a smooth cut without glitches. Chip removal is not easy to stick to the tool.4. Adapt to several kinds of cooling conditions, for example oil mist, water, oil, air cooling.Specification:Shank Type: Round ShankTool Flute Type: SpiralRock Well Hardness Grade: 63-66 HRCTwist Drill Bits Diameter: 0.6mm(0.024"), 1mm(0.039"), 1.1mm(0.043"), 1.2mm(0.047"), 1.4mm(0.055"), 1.5mm(0.059"), 1.6mm(0.063"), 1.8mm(0.071"), 2mm(0.079"), 2.2mm(0.087")Material: HSS(High-Speed Steel)Finish: Titanium CoatedShank Diameter: 2.35mm / 0.09-inchTotal Length: 50mm / 1.97-inchDrill Bit Length: 21mm / 0.83-inchPackage Content:10 Pcs x High-Speed Steel Twist Drill BitTips: When drilling, the drill bit should be drilled reciprocally, not all the way into. The reciprocating drilling can bring the debris out to avoid blocking the hole. When it is about to be drilled through, it should be played on the other side, not once, to avoid the edge of the drilling collapse.