The Marshall Excelsior MER613-12 is a high-pressure propane feed line designed for use in RVs, trailers, and campers. This 12-inch line features a 3/8 inch female flare swivel end size and is UL/CGA approved for safety. It also comes with thermal protection to prevent accidental fires and is branded by the reputable manufacturer Marshall Excelsior. This product is a single unit and does not come with a regulator. Additionally, it carries a California Prop 65 warning due to potential chemical hazards.F-9