M-Rock's patented ms p-series stones are built for beauty, durability and ease of installation. No mortar needed and simple to install - just stack and lock stones together with the built-in rail and the patented concrete locking system, then screw the panel to the wall - it's that easy. Installs with screws into most substrates in any weather; built-in rail provides innovative and integrated air and weep system. Installs with screws - no mortar needed; simply stack and screw to the wall Beautiful 5 in. x 20 in. (patented) stone panels perfect for DIY projects and all levels of the construction industry; no mortar and no mess Class A fire-rated; durable interior and exterior concrete-based product; made to look and feel like natural stone; safe for use around fireplaces or chimneys, no direct flame Cut easily with a dry masonry blade to meet your specific project needs Increase the value of your residential or commercial property by installing this M Rock Easy Stack Montgomery Manufactured Concrete Ledge Stone Flats.