Dilute the Mr. Color with the exclusive thinner. The standard paint-to-thinner dilution ratio is 1:1.5 to 2 for painting with an air brush. Use the Leveling Thinner for painting with an air brush. (It is also available for brush painting.) It improves the paint flatness and provides glossier surface, since it contains retarder. It also provides even mat surface when used for mat paint. Tested and certified radiologically inert.