Mapei UltraFlex-2 Gray Mortar is a 50lb bag of professional-grade, single-component, high-performance, polymer-modified thin-set mortar for interior and exterior installations of ceramic, porcelain and dimensional natural-stone tile. This mortar has a high content of unique dry polymer, resulting in excellent adhesion to the substrate and tile.FEATURES AND BENEFITS•Polymer-enriched for high performance and deformability •Smooth and creamy consistency for easy applicationWHERE TO USE•Most interior/exterior residential installations on floors and walls •Most interior/exterior commercial installations on floors •Most interior commercial installations on walls •Installation of ceramic and porcelain tile, quarry tile, pavers, Saltillo tile, and many types of marble, granite and natural stonePrior to beginning your project, please consult the manufacturer's installation guide