Mercedes W123 differential with a final ratio of 3.46. In excellent usable shape. Side cover seals don't leak.
Oil that was drained was clear and not dark, had regular maintenance. Out of an older 300D wreck, speedo was gone so no idea how many miles on it, but it turns and works as it should, looks clean inside.
Unlike most MB W123 diff covers, this one has cooling fins on the rear cover.