Tank to Regulator Adaptor is used to convert a CGA-580 Nitrogen/Argon tank to a CGA-320 Carbon Dioxide (CO2) regulator. You can use your standard CGA320 regulator on a CGA580 Argon-Helium-Nitrogen tank with connection of CGA580. This adaptor is solid brass with a easy-to-seal CGA580 O-RING Connection.