Auto Air Iridescent Colors are semi-opaque colors with a semi-gloss finish. Iridescent Colors are recommended for use with airbrush sizes 0.5mm or larger. A 0.3mm size airbrush may be used when colors are thinned with Auto Air Reducer. Iridescent Colors are best used over Auto Air Base Coat Sealer Dark or 4200 Series Deep Black Graphic Colors. Colors may be used alone for iridescent finishes, as a base for 4200 Series Transparent Graphic Colors for custom blends, or as base for the 4600 Series Candy Colors . For custom iridescent blends, apply 2-6 light coats of 4200 Series Transparent Colors over Iridescent Colors.