SIMPLE GREEN Oxy Solve House and Siding Pressure Washer Concentrate 1 Gal. Meets the rigorous criteria of the U.S. EPA’s Safer Choice Program. Safer, non-toxic and biodegradable formula. Uses the natural power of peroxide to lift grime and remove stains. Eliminates discoloring from algae, moss, mold and mildew on vinyl, brick and cinderblock. Cleans black streaks from stucco and siding.