That's a rebranded Engel MRFT40, made by Matsushita. I have one, bought in 1981. Its never been touched (no R&M, zilch!) and still works perfectly as a refer or as a freezer. When not 4WD/camping it was plugged into AC in the garage as a beer fridge. They were the gold standard way back, and may very well still be.
Think twice before selling it. Very flexible piece of kit to have, and one day you might want some extra capacity back on the boat.
These days in Oz the latest 40 litre model in metal like that, which uses a bit less power, sells for over A$1200