Description:

Twist Drill Bits: Cutting edge diameter: 4mm / 0.157"; round shank diameter: 4mm / 0.157"; cutting edge length: 43mm / 1.69"; overall length: 71mm / 2.8"; split point: 135 degree. Used with hand drills, drill presses, bench drills, machining centers, CNC lathes, etc.. M2 High Speed Steel: M2 high speed steel (HRC64-66) drill bits offer excellent heat resistance and hardness for durability and longevity, as well as good cutting performance and accuracy for clean, precise holes with minimal burrs.. Black & Gold Finish: Black nitride and gold titanium dual coatings can apply lubricant better for smoother drilling and are more durable and corrosion resistant. Sharp cutting edges provide neat and smooth cuts. Large spiral grooves facilitate the export of metal chips.. Wide Applications: Drill bits produce holes in stainless steel, cast iron, A3 steel, carbon steel, aluminum alloy, copper, wood and plastic. Most suitable for drilling metals with a hardness less than HRC38, and cannot drill quenched metals, tiles, concrete, walls, stones.. Tips: Use an appropriate lubricant to reduce friction and heat build-up. Controlling the speed is very important, recommended speed: 100-800rpm/min. The larger the diameter, the slower the speed required. If the hole is larger than 6mm, first drill a small hole with a 3.2mm-4mm drill bit, and then use a larger drill bit to enlarge the hole..