HD6500EXT Concrete Sealer is a clear, gloss, fast drying, water-based, non-yellowing, pure acrylic concrete lacquer style sealer designed for exterior concrete and interior concrete. HD6500EXT offers improved resistance to rain, the sun, freezing temperatures, stains, and other pollutants that sometimes can be hazardous to concrete. Applying HD6500EXT to exposed aggregate will also help to eliminate loose pebbles and premature wear. One gallon covers approx. 250-350 sq ft depending on the porosity of the substrate. Two coats required for opaque coverage, recommended. Matte additive can be used with this product. Not recommended for garage-use.