Is a High Performance Broad-Spectrum Concentrate that Effectively and Thoroughly Removes Exterior Black Roof Stains / Streaks, Fungi, Algae, Mildew, Moss and Lichen in a “No Rinse” Biodegradable Application Using only Sun, Rain and Wind. For Use On Asphalt Shingles, Roof Tiles, Shake, Slate, Stucco, Brick, Concrete, Masonry, Pavers, Landscaping Stone, Keystone, Limestone, Sandstone, Bluestone, Fences, Composite Wood and Wood Deck Surfaces. Because an Algae Free Surface is More Than Being Visibly Clean!