This high-tech formula halts residual rust in its tracks and converts it into a black protective polymeric coating that eliminated the need for sanding. The converted protective coating is a suitable primer, compatible with most top coats. Additionally, the protective coating will seal the surface against moisture to prevent future rust growth. Simply remove loose rust with a wire brush then apply Rusfre Rust Converter/Sealer. Allow to dry, then top coat it with a quality coaitng. Single component; no more mixing. Paintable.