This assembly, exclusive to Amana Tool®, has multiple-radii cutters that enable you to roundover both top and bottom edges in just one pass, using either of two radii. Switch the positions of the cutters to change the cut radius. Interchangeable spacers alter cutter spacing to accommodate different stock thicknesses from 3/8" up to 1-9/16". The assembly includes the arbor, a pair of multi-angle cutters, pilot bearing, spacers, and shims. Replacement parts are available separately. For best results use in a router table!