It's all 8AWG, anything thicker was overkill since the fridge will plug straight into the battery at a socket on the battery box. Really the Anderson plugs at either end of the trailer are for the solar panels to plug into and they will top out at around 10A at most.
The main reason I decided to hook it up to the Jeep for charging is because I'll have my 50lt Waeco in the trailer when on the road, but it will already be cold and the battery full charged so I don't expect it to be a big load, plus the Jeep was already setup for it
I also have a CTEK for those times when the battery needs a top up and there is power around.
Cheers
Steve