Green Seal™ Certified hard water scale remover that is safer than HCl or Phos acid cleaners. Unique deactivated acid activates on contact with soil. Safer scale remover with a health rating of 1 in use. Kicks soils like an acid to remove built-up hard water scale, rust, soap scum, mold stains and mildew stains. Worker friendly with a low odor that leaves no harsh acid fumes. Dilutes 3 ways based on soil load.