Natural Holding Tank Deodorant & Cleaner: Effectively controls ordors, Only 4 onces will treat up to 40 gallons of tank capacity. Environmrntally safe. A special blend of bioegradable ingredients controls orders without formaldehyde, glutaraldehyde, quaternary salts or other harsh chemicals. Breaks down waste and toilet tissue. Fresh scent. Non-staining liquid formula combines powerful order control and cleaners with a pleasant, floral-mint scent. Easy to use. See-through window stripe and 4 oz. increment marks make measuring easy. Size: 8 oz., 2-pack.