Marshall Excelsior ME425 Propane Adapter Fitting . Male POL inlet with O-ring x 1/4 inch female inverted flare auxiliary inlet with check valve x 1 inch 20 MNPT outlet x 1-5/16 inch male ACME Brass Fitting. This fitting allows towable RV owners the choice of hooking up to an auxiliary propane cylinder so they can stay where they want, as long as they want, without having to periodically refill their propane tanks(s).
