"Single Stage" system is nothing more than a solid or metallic color applied over a primer/sealer. Known as a "S/S system," there is no clear paint necessarily involved in this system. Because the color must be "color sanded" with 2000 grit 3-M paper (used wet) to remove small flaws, it is usually best to only use solid colors. Sanding a metallic single-stage color almost always results in "splotches" in the color because some of the metallic paint is removed during the color sanding step.
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