The Twofold tables are made from aluminum, which naturally resists corrosion and does not develop the rust commonly associated with steel. The powder-coated finish seals the surface against moisture and UV, and the marine-grade hardware is specified for the conditions outdoor furniture actually meets. No outdoor piece is fully immune to extreme salt-air settings over the long term. A periodic fresh-water rinse is the simplest thing you can do to keep the finish looking like itself.