Custom Building Products Custom-Blend Thin-Set Gray Mortar Mix, 50 lb. an economical formula designed to provide strong bond strengths suitable for most tile projects, especially for floor installations. This non-modified mortar is made from Portland cement and is i for both interior and exterior use. It effectively bonds a wide variety of materials including vitreous, semi-vitreous, or absorptive tile, ceramic, mosaic, quarry, pavers, cement, porcelain, brick, mini-brick, precast Terrazzo, and natural stone to substrates such as concrete, masonry, gypsum wallboard, wonderboard, backer boards, exterior grade plywood, existing ceramic tile, asos- vinyl flooring, and plastic laminates. Some applications may require the use of acrylic mortar Admix. This product is not suitable for use over hardwood, luan, plywood, parquet, particle board, cushion, sponge-back, asos-containing vinyl flooring, metal, fiberglass, or OSB panels. Coverage is approximately 85 to 95 square feet per 50 lb. bag when applied with a 1/4" x 1/4" notched trowel. It exceeds ANSI A118.1 and A118.4 specifications and should be allowed to cure for a minimum of 24 hours before grouting or light foot traffic. Clean up is easy with water immediately after application. The product comes in a 50 lb. bag with a shelf life of 15 months. Model Number: CBTSG50