Blue Anodized Aluminum Tube Fitting (AN 818), -04 JIC 37 deg Flare Nut

For a standard -04 JIC 37-degree flare connection, yes this is the correct nut. It follows JIC standards so it'll mate up with any AN/JIC flare tube assembly at that dash size. Eaton Aeroquip makes this one, so fitment on a properly flared tube end should be straightforward.