House of Kolor RU313 Very Slow Reducer (RU313.Q00) is a premium urethane paint reducer formulated for use with House of Kolor Kosmic Kolor® urethane enamel systems. Designed specifically for high-temperature and large-panel applications, RU313 provides a very slow evaporation rate that improves paint flow, leveling, and gloss while minimizing dry spray, overspray, and orange peel. Perfect for automotive refinishing, collision repair, custom paint, and restoration projects, this professional-grade reducer delivers excellent atomization and consistent performance when used with compatible House of Kolor primers, basecoats, and clear coats, resulting in a smooth, show-quality finish.