Use 4-wing Slot Cutters for the cleanest possible grooves in hardwood, softwood, plywood or composites. These cutters are a great choice to mill slots and grooves for T-moldings, spline joints, tongue & groove joints and many other applications. Should be used with Freud's slotting cutter arbors 60-100 for 1/4" shanks and 60-102 for 1/2" shanks, and 62-108 bearing.