Granville Rust Converter is the rust convertor used by the oil and marine industries, the MoD and NATO. It is used to stop corrosion in environments far more severe than your car will ever see . . . and it WORKS. Drying to a tough gloss black finish it can then be top coated with most paints. Environmentally and ecologically safe. Acid and lead free. Non-flammable. MUST be applied to rusted ferrous metals. Kills old rust and stops new forming. 3 Sizes Available: 250ml , 1 litre , 5 litres . Still unsure? Read our customer review here .