Solid Carbide Spiral Flute Plunge Router Bits for Solid Wood Spiral bits combine a shearing action in cutting with an augering action in chip clearance. The shearing action yields an especially clean & accurate cut, while the augering action clears chips from the cut. The up-cut shears from the bottom up, pulling chips from the bottom up, thus allowing deeper penetration with less stress on the tool. An excellent choice for mortising. Unique carbide grade for longer lifetime in abrasive materials Produces a superior finish and longer tool life Razor-sharp cutting edges/polished flutes' Can be used with hand-held, table-mounted portable routers and CNC machines Industrial qualitySpecially designed for speed and finish when working with solid wood. The combination of acute spiral flute shear angles with face ground helix yield high feed rates, fast plunge action, quick direction changes, deep penetration and mirror finish.