The Freud Quadra-Cut technology gives you smooth cuts with virtually no re-work or sanding necessary. Freud's innovative 2+2 Panel Raising bits feature 2 small wing cutters with downward shear to eliminate chipping and splintering of the shoulder, and two large wings with upward shear for smooth reveal and tongue. The patented technology allows for faster feed rates as well. Use 5/8 carbide height router bits with 3/4 stock: 1/2 carbide height for 5/8 thick stock. Use only on table mounted routers!