Zinsser Watertite Latex-Base 3 Gallon Low VOC Mold and Mildew-Proof White Water Based Waterproofing Paint is a modified acrylic copolymer concrete and masonry waterproofing paint and finish. Designed to form an impermeable barrier to water on interior and exterior, vertical or horizontal, concrete block and cast-in-place concrete. Stops moisture from entering basement or cellar walls and stops water from exiting when applied to canals or holding basins.