I'd like to list all of the Electrical Adapters that are available for RV's here.
To start the list this is a Straight 30F/15M Amp Adapter:
Most of would need this adapter to connect our 30 amp plug to an outlet at home or at a campground that only has 15 amp service. You'll only get 15 amps even though you are using your 30 amp cord.
This next one is a 50 Amp Male to 30 Amp Female Adapter:
You'd need this if the RV Park only has 50 amp service and your RV has a 30 amp cord.