If the fitting is on the tank then a regulator is not required. My rv regulator is hooked next to the tank so I put a tee about 3 ft downstream and bought a regulator to connect to portable tanks directly. If I shut off rv tanks I can run the regulator/portable tank only. (I did install a gate valve between the rv regulator and the tee to be safe) I can also run a hose from that tee directly to my champion lp genset and run it off the rv system if needed. When running generator from portable tanks you need a regulator anyway so I got a residential regulator and threw away the cheap junk regulator and hose from champion and have 25 ft real propane hose. It is expensive braided hose about $6 a ft but strong enough to tow a small car!! Hope I explained this clearly enough.
