Champion equips their generators for several different kinds of propane hoses.
One version has just a conventional high-pressure regulator on the hose (which feeds a second low-pressure "zero demand" regulator located inside the generator itself).
With this type, the original hose can be discarded, with the generator instead connected to the RV propane system at any point after the RV's regulator.
Basically, the RV's propane regulator takes the place of the regulator mounted on the original hose supplied by Champion.
Another version has both the high- and low-pressure regulators installed on the hose (in which case there is no other regulator inside the generator itself).
This type can NOT be directly connected to an RV propane system, since it would lack any means of automatically shutting of the propane flow if the engine stopped running.