Specification:

Material: High Speed Steel, Cobalt
Finish: Black & Gold Oxide Finish
Shank Type: Round Shank
Bit Diameter : 4.2mm / 0.17", 6.8mm / 0.27"
Flute Length: 43mm / 1.69", 58mm / 2.28"
Shank Diameter : 4.2mm / 0.17", 6.8mm / 0.27"
Total Length : 75mm / 2.95", 108mm / 4.25"

Package:
5 x 4.2mm Twist Drill Bits
2 x 6.8mm Twist Drill Bits

Description:
1. High-speed steel straight shank drill bits are good for most general purpose applications, offering a combination of hardness and toughness for wear resistance.
2. Sharp spiral flutes provide neat and smooth cuts. High cutting edge strength, fast cutting speed. Spiral groove facilitates the export of metal chip, saving time and effort in operation. Common flute and overall length for minimal adjustment during tool changes.
3. Premium gold titanium and black nitride dual coating can apply lubricant better for smoother drilling and is more durable and corrosion resistant than the regular black surface.
4. For use in a wide range of stainless steel, aluminum alloy, iron, copper, brass and metal materials.