I highly advise running a 50A 220V RV receptacle. Both legs are 110V but from different legs in the panel with a two pole 50A breaker feeding the RV plug. you will need 3 ea 6ga wires (black red white) and one 8ga wire (green) to complete this properly. You should be able to get this in romex or run separate wires in conduit. I used a SO cord that fed a 50A temp construction power box for my RV outlet. I use the breaker for my disconnect.
From AMAZON GE Energy Industrial Solutions U054P Midwest Electric Outdoor Raintite Receptacle Enclosure, 120/240V, 50-Amp
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