For a luster worthy of a fine yacht, choose a translucent film-forming finish. Spar varnish has been the traditional choice for this effect, but it's a bear to apply and maintain. Sikkens's two-coat Cetol Dek Finish (sikkens.com
), shown at left, offers the same look but with a film that's more breathable and flexible, and it has more sun-blocking pigments than a varnish. Brushing on a refresher coat is easier, too. Just wash it, and apply the new finish when it dries.