3-in-1 cleaner cleans all wood types including redwood, cedar, mahogany and other highly resinous woods. While many cleaners can darken woods, this deck cleaner actually helps restore their natural color and beauty. Removes stains from dirt, mildew, algae, and fungus. Eliminates tannin, rust stains, and mill glaze on new wood. Brightens and restores wood's natural beauty. Use before waterproofing: decks, fences, outdoor furniture and other exterior wood surfaces.