254SMO (Ni 17.5-18.5%, Cr 19.5-20.5%, Mo 6-6.5%, Cu 0.5-1%, N 0.18-0.22%) delivers excellent pitting and crevice corrosion resistance due to its high molybdenum, chromium and nitrogen content; the copper addition further improves resistance in certain media. Used in seawater and desalination, pulp bleaching and aggressive chemical processing.