Electrical connection box help needed for weekend trip

Power distribution block available at most big box hardware stores and Ace hardware.
Come in various configurations. Two pole versions of these are good Power distribution blocks.
They need to be protected from weather like most.
Use an ample amount of electrical corrosion grease on all conductors.
It was common for manufacturers to install 4 inch octagon or four square boxes under the tongue of rigs. There are rated for that kind of area as they are only NEMA 1. But they did it anyway!