CGA-540 TO CGA-540 Oxygen Transfill Adapter for trans-filling portable oxygen tanks from large H tanks at 2200 PSI.  Yoke accessory available as accessory item ($60).

Features:
        All parts are rated at 3000 PSI.
        All parts are new and cleaned for oxygen service.
        Pigtail is a 4 ft. high-pressure braided stainless steel flexible hose .
        Pressure release valve and gauge are at the midpoint of the hose.       
        Gauge is rated to 4000 PSI
        Pressure release needle valve for added safety and convenience
        Ends are a CGA-540 female
        Check valve eliminates tank contamination