The U.S. Coast Guard has expanded their approval of Lokring 316L SS40 fittings and MAS-3000 Carbon Steel fittings from ¼” through 3” in both Stainless and Carbon Steel.
These fittings have been designated as acceptable for marine piping applications subject to the limitations of of Subpart 56.30-25 of Title 46 of the Code of Federal Regulations (46 CFR).
View the U.S. Coast Guard Approval Letter.