Solid Carbide Spiral Router Bits Spiral bits combine a shearing action in cutting with an augering action in chip clearance. The shearing action yields an especially clean & accurate cut, whilethe 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 qualityThese router bits are great for production settings and excellent for creating grooves and dado cuts in softwood, hardwoods, plywood and composite materials. Primarily used on CNC machines and other automatic routers.