5083-H116 and 5083-H321 are both variants of the same aluminum alloy. The magnesium content of H116 aluminum alloy shall not be less than 3.0%, and the state after anti-corrosion treatment; H321 aluminum alloy with a magnesium content of not less than 3.0% after hardening.

H116： Magnesium content ≥ 4%, with good mechanical properties and resistance to peeling and corrosion.

H321 has good corrosion resistance and more stable performance. It has higher hardness and better stability than H116 aluminum plate, and has good anti-corrosion performance after coating. 

5083-H116 and 5083-H321 can both use marine aluminum plates.

5083-H321 Aluminum Plate