What is this nozzle fitting?

[Mrcrowley]

I found this garden hose type nozzle on trailer in middle of the hitch has a cap on it . It would fit a garden hose on it no valve .
Is this a drain of some sort?

[CanoeStream]

It might be for water hose at a campsite with a water hookup. My '74 Argosy had a threaded plug on a lanyard to block it while underway. Got a picture?

[overlander64]

If it is on the 1977 Sovereign, it may be the Vacuum Port for the Excella HydraVac Disc Brakes. It could also be a fixture added by a previous owner to fill the fresh water tank.

Kevin

[Mrcrowley]

Originally Posted by overlander64

If it is on the 1977 Sovereign, it may be the Vacuum Port for the Excella HydraVac Disc Brakes. It could also be a fixture added by a previous owner to fill the fresh water tank.

Kevin

Ok I bet it for the old brake system because I filled the water and the cap was off no water leaked out.