Solid Carbide Spektra Extreme Tool Life Coated Double Flute Up-cut Ball Nose SpiralsUsed for carving, decorative doors and sign manufacturing. These Up-Cut Ball Nose Spiral Router Bits leave an excellent finish and expels chips quickly. Produces a superior finish and longer tool life Two razor-sharp cutting edges/polished flutes' Industrial quality Excellent for cutting aluminum and non-ferrous materialsExcellent for cutting: MDF Sign Foam Soft/Hard Plastic Soft/Hard WoodSpektra bits feature a nACo nanocomposite coating with an extreme nanohardness and heat resistance. With a brilliant distinctively-tinted coloring nACo provides additional improvements in four critical aspects of router tooling. nACo coating is a micro-thin ceramic coating which enables the tool's cutting edge to retain crucial sharpness and lubricity. This provides longevity and produces cutting results of the highest quality. Coating prevents high heat and oxidation which is detrimental to cutting tool performance. Multi-colored hues, while attractive, will dissipate upon use and yet coating will remain fully effective. Multi-colored hues, while attractive, will dissipate upon use and yet coating will remain fully effective. nACo offers approximately 4,500 Vickers for impressive solid hardness on cutting areas of the tool, for an increase up to 2.5 times compared to uncoated bits.Note: Blue based color dissipates immediately upon use. nACo nanocomposite coating will not wear off.