Use this router bit set to build beautiful custom entry doors and interior passage doors. With true rail-and-stile construction, you'll get rock-solid joints that last a lifetime. The bits are larger than standard rail and stile bits, and are capable of cutting joints for doors up to 1-3/4" thick. To make thinner interior doors (1-3/8" thick), simply remove the spacers. You can also mill a tenon of virtually any length! To do so, the top cutter and bearing of the rail bit is simply unscrewed from the lower cutter and shank. No need to remove the bit from the router or change the height of the cutter!