Zymol Carbon Wax is my choice. Sure it's pricey ($50), however, it's worth it.
Zymol recommends Carbon Wax for the following finish colors: black (acrylic, lacquer or metallic), medium and dark brown, medium and dark blue, medium and dark green, orange, red, burgundy.
Unlike off-the-shelf liquid waxes and synthetic sealers, Zymöl Carbon Wax brings out the richness of dark colors instead of showing like a glass layer on top of the paint.
One thing to note.... The jar has to be refrigerated when not in use.
