EAGLE AMERICA Slot Cutter Router Bits are 3 and 4 cutters that are interchangeable and can be combined and stacked on the same arbor giving you a wide variety of cutting possibilities. Make sure cutters are put on the arbor in the proper cutting direction and always use the supplied spacers between the cutters and bearings. All cutters carbide tipped. Cutters and arbor assemblies sold separately. Made in the USA