It is a concentrated, multisurface cleaner that is packed with Oxygen-Power that gets rid of mold and mildew stains. It was formulated to quickly remove stubborn, embedded mildew stains that tough mold and mildew can leave behind after cleaning. Moldex® Deep Stain Remover does not contain harmful bleach, ammonia, or other harsh chemicals. It is nontoxic, has little odor, and will not harm plants or fabrics like traditional cleaners.