Input: 115 V.A.C.
Output: 12 V. AC
This is what your shore power cord connects to. It allows you to run your 12 volt direct current appliances (lights, water pump, fan) from 110 volt alternating current campground supply instead of
your 12 volt battery
This is a very small and simple unit.
A new unit would be higher AMP rating: Converters at Camping World
The new ones are much more expensive.