Vanlife: understanding breakers at the RV park

You pull up and find a box like this. But what does it mean?

Left is 50A, middle is a 30A, right is 20A.

The 50A has the double pull breaker, 30A to right of that, 20A is far right breaker.

The middle outlet is the standard 30A RV plug. It’s pretty much the most common for many vans.

You need an adapter like this to use a 50 amp plug.