Two flute straight cutters produce a cleaner finish than the single flute cutters and are suitable for grooving, rebating, morticing and drilling. Use Tungsten Carbide tooling when working with abrasive materials such as chipboard, MDF, plywood and certain hardwoods. Two flutes give a clean finish to cut edges. 1/4in Shank.C = 25 mmD = 20 mm 25/32in