The decorative keystone adds bold detail to entryways, windows and mouldings. Decorative urethane keystones also install easily for excellent results, which offers a cost-effective alternative to traditional masonry and trim. This keystone features a classic recessed panel. It is designed for use with flat mounding (FLT159). Update your decor or create something entirely new with the addition of a decorative urethane keystone. The recessed keystone is precision molded in high quality polyurethane material. Urethane, a rigid, high-density material, performs exceptionally well in exterior applications. The recessed keystone will not warp, crack, peel or decay.