The Prova railing system from DOLLE offers interior and exterior railing systems that are component based, easy to install, and beautifully designed. The Prova railing system offers several different configurations that provide a sleek, contemporary, custom look at DIY pricing. Prova railings are perfect for any home - creating dramatic sightlines outside, and making small spaces seem larger inside.Prova PA13b anthracite side mount post extenders are used to gain an additional two inches of clearance for Prova side mount posts. Designed to work with both 36-inch and 42-inch Prova anthracite posts, these spacers will offer a total of 2.88 inches of clearance from any obstruction. The Prova PA13b anthracite side mount post extenders are constructed of heavy-duty steel with a matte anthracite powder coated finish.Give yourself greater flexibility when using side mount posts where stair treads extend. Spacers come two per pack. One pack is needed per side mount post that needs extending. No special skills required - Prova is designed for easy assembly with basic hand tools. Color: Black.