Polymer modified, Portland cement mortar system formulated to provide excellent adhesion to interior surfaces without the addition of a latex additive. Use to adhere glazed and unglazed ceramic mosaic, glazed wall tile, quarry, terrazzo, cement bodied tile, high lug tiles and pavers to properly prepared interior surfaces such as exterior grade plywood and many resilient flooring surfaces. It also offers increased bond strength when adhering to conventional thin set mortar substrates such as concrete, concrete block, wonderboard, gypsum drywall, and existing ceramic tile. Interior use only. Not recommended over cushion resilient flooring, hardwood or parquet flooring, particle board, wafer board, masonite, metal or plastic. Coverage is dependent upon substrate, tile, and size of notched trowel. Average coverage is approximately 2 sq. ft. per lb. Allow to cure 24 to 72 hours before grouting. Clean up immediately after use with water. No. MTSG25: 25 lb. bag, gray No. MTSG50: 50 lb. bag, gray No. MTSW50: 50 lb. bag, white