Another tread about filling RT water tanks prompted me to share this.
I did not like the door jamb fill ports for my RT.
If I tried to fill quickly I ended up with water inside the vehicle, and I didn't like the slow fill time involved and still had some water spill.
So, I bought an automatic shut off nozzle. Using the pressure regulator on the hose I can lock the nozzle on and go about other things. It shuts off without any overfill spill.