Use this rail and stile router bit set to create beautiful door frames for glass panel, flat panel and raised panel doors. Rockler rail and stile bit sets are manufactured to exacting standards and create perfectly matched cope and stick joints. The one-piece cutting edge allows you to achieve a perfect fit without having to disassemble an arbor and install shims. With ball bearing guide, you can even use a template to build doors with curving rails. 5/8" Bearing. 1/4" x 3/8" Groove. K10 and K20 grade carbide for clean cutting action. Final sharpening with 600 - 800 grit diamond wheels. Precision balanced for smooth operation. Baked-on anti-stick coating to reduce pitch and resin buildup. If you are not 100% satisfied with these bits, send them back for a refund.