I put it on before last season. After fishing last year in puget sound , hood canal and moored for 7 days in canada salmon fishing . I didnt have to polish once. I was actually planning on doing another coat this year but dont need it. Follow the directions carefully and get all the oil and buffing compounds off after polishing and you shouldnt have a problem. Another product I really like is saltaway you can get it at sportco or 3 rivers. You put the applicator on the end of your hose and wet your boat and trailer down. Then wash with soap and water. Then rinse with fresh water. Their is a selector knob on the applicator for either soap or water. I even flush the motors with it. It makes the salt crystals that dry one the boat on the tow home disolve easier.