SPF Cast Iron Threaded Fittings Material Specifications Dimensions: ASME B16.4 Class 125 Material: ASTM A126 Finish: Black or Hot Dip Galvanized per ASTM A153 Class A Threads: NPT per ASME B1.20.1 Agency Approvals: All cast iron threaded fittings are UL/ULC Listed and FM Approved.