They are definitely not oiled, the black is painted and the oak is stained then clear coated, here are some pics below of my k9's that were black when I bought them new, I wanted oak but only black was available at the end of the k9's run so I changed the color the next day after I purchased them 26 or so years ago and they still look good today, I taped them up with news paper so the drivers wouldn't get any dust on them and sanded them down with an electric sander then I stained them in walnut and put 5 coats of polyurethane on them, I left the black color in the fluted edges, they were actually not that hard to do, I think they turned out nice.