HighlightsSealed and 100% Waterproof - shower bays use XPS extruded foam board, cement mortar, waterproof coating triple waterproof substrate, 100% sealed and waterproof, which not only can protect the wall and extend the service life of the wall but also effectively prevent water penetration into the wall, keep the indoor dry and sanitary. NOTE - This product is not for direct use. Surface layer, like tile, must be applied to the surface before use!!!High-Quality Material - The (HCFC-free) XPS