This 2-piece set lets you create beautiful wooden windows. In addition, this set also produces perfectly matched 1-3/8” rail and stile parts for custom made interior doors. Bits feature super-strength superior steel bodies, Non-Stick Orange Shield Coating and cutting edges made of SinterHip Hi-Density Industrial Chrome Carbide for a long-lasting performance. Not for use on hand-held router. Use them on router table. After a test performed by Wood Magazine, CMT orange bits have been rated the first overall router bits compared to other brands.