The Guardian Fall Protection Ridge-It Tile Anchor is designed for installation on wood substrate beneath tile roofing. This Ridge-It model is manufactured with 1 D-ring and is 18 in long. It is composed of stainless steel and zinc-plated steel for maximum durability, and is compliant with all applicable OSHA and ANSI regulations. Ridge-It Anchors are easy to install, and are ideal for both residential construction and maintenance work.