Schluter Kerdi Flex is manufactured using high-density polyethylene (HDPE), which does not rot and is highly resistant to solutions containing salts, acids, and alkalis, as well as many organic solvents, alcohols, and oils. Its resistance to specific stresses can be provided if concentration, temperature, and exposure time are known. Schluter Kerdi Flex is waterproof and resists the transmission of vapor. The material is inert, non-toxic, and physiologically safe. Schluter Kerdi Flex also meets the American National Standard for Load Bearing, Bonded, Waterproof Membranes for Thin-Set Ceramic Tile and Dimension Stone Installations (ANSI A118.10) and is listed by cUPC. Schluter-Kerdi-Flex’s uncoupling function protects the ceramic or stone tile covering from the aforementioned deformations by neutralizing the differential movement stresses between the wood structure and the tile, thus eliminating the major cause of cracking and delaminating of the tiled surface. Therefore, FLEX can replace a second layer of plywood in most applications. Schluter Kerdi Flex provides reliable waterproofing in interior and exterior applications. Its polyethylene composition protects the substrate from moisture penetration, which is particularly important in today’s building environment where most substrates are moisture sensitive. The distinguishing feature of Schluter Kerdi Flex is the existence of free space created by the configured channels on the underside of the matting. The free space provides a route for excess moisture and vapor to escape from the substrate that could otherwise cause damage to the tile layer above. Thus, FLEX effectively manages moisture beneath the tile covering.