These ends are specifically for use on our SB stainless hose assemblies. Prices include attaching charges (standard assembly part #'s are SB321SizeXLength-Fittings). All fittings are installed and tested by certified welders to section IX of the ASME boiler and pressure vessel code. They are available in carbon steel (C), 304 stainless (4), or 316 stainless (6). Carbon steel is NOT designed for low temperature applications below -29°C (-20°F) - use stainless for applications subject to lower temperatures.