Winsor & Newton Professional slow drying medium maintains no color shift from wet to dry when used with Winsor & Newton Professional Acrylic. Slows drying to give more working time of color for extended blending and manipulation, a ratio of 1:1 color to additive volume doubles the drying time. Maintains color viscosity and has no effect on the finished color when dry. Details:Available in multiple sizesSlows the drying time of acrylic color Maintains color viscosity Has no effect on finished color when dryFor use with Winsor & Newton Professional Acrylic