Rust Stain Remover is the best way to eliminate unsightly rust stains from boats, RVs, exterior walls of homes or wherever else they may form. The formula begins working on contact, dissolving the oxidation that causes these stains. Easy to use; spray directly onto stained area and rinse off; no heavy scrubbing needed. DIRECTIONS: Spray Star brite Rust Stain Remover directly on surface to be treated. Let product work until stain is gone before rinsing area with fresh water. Deep stains may require a second application and light scrubbing with a brush or cloth. To help prevent future rust stains, apply a protective coating of Star brite Polish to cleaned area to seal surface pores. Avoid contact with fabric. Test area to be cleaned for colorfastness in an inconspicuous area before proceeding with overall cleaning.