Economical formula with good bond strengths for most tile projects and is recommended for floor installations. Non-modified mortar is formulated of Portland cement for interior and exterior use. Use to bond vitreous semi-vitreous or absorptive tile ceramic mosaic quarry pavers cement porcelain brick and mini-brick precast Terrazzo and natural stone to concrete substrates masonry gypsum wallboard wonderboard backer boards exterior grade plywood existing ceramic tile asbestos-free vinyl flooring and plastic laminates. Some applications may require using acrylic mortar Admix. Not recommended for use over hardwood luan plywood parquet particle board cushion sponge-back or asbestos containing vinyl flooring metal fiberglass and OSB panels. Suitable for use with vitreous semi-vitreous or non-vitreous tile ceramic mosaic quarry cement body tile impervious porcelain and glass tile brick and stone veneer cement-based precast terrazzo natural stone tile. Approximately 85 to 95 sq. ft. per 50 lb. when applied with a 1 4 x 1 4 notched trowel. Exceeds ANSIA118.1 and A118.4 specifications. Allow to cure for a minimum of 24 hours before grouting or light traffic. Clean up immediately with water. 50 lb. bag.