Amana 46200 Solid Carbide Spiral Plunge 1/8 Dia x 1/2 x 1/4 Inch Shank x 2 Inch Long Down-CutSpiral flute 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 Down Cut cuts from the surface down leaving a smooth edge at the surface. Special unique carbide grade increased clearance geometry and razor sharp cutting edges with polished flutes provide a superior finish and longer tool life especially