Evapo-Rust is a product of extensive research, Evapo-Rust rust remover is an environmentally safe water based product that has been proven to make even deep rust disappear without any scrubbing. It's so easy to use; anyone can restore their rusted steel tools, auto parts and household items to like-new condition. 1 gal. de-rusts up to 300 lbs. of steel (about 0.5 lbs. of rust). Evapo-Rust will not harm metals, rubber, plastic, PVC, viton, most paints or un-rusted steel. Best of all, Evapo-Rust is safe to use. It's non-toxic, non-corrosive, non-flammable and contains no acids, alkalis or petroleum solvents. Evapo-Rust is even biodegradable.