If you are asking about the alternator cases, they were bare aluminum, as already stated. I have a hint if you want to keep them looking like new and not tarnishing over time. Have a shop take the alternator apart, and then glass bead the aluminum housings to get them good and clean. Then mix a good amount of flattening agent to some clear coat. The flattening agent knocks the gloss down on the clear and since it is white, it adds a bit of tint to the clear. Be sure and spray the pieces with the spray gun far away from the pieces so that the clear is much dryer than you would normally spray it to give it a textured finish. It may take a little experimentation to get it right. But with the right combo, the finish looks nearly perfect to bare aluminum. And stays that way.