OPEN Acrylics feature uniquely relaxed working characteristics and a remarkable ability to resist skinning and remain wet on the palette during long painting sessions. Working time varies according to how thickly the material is applied. Thin applications â€œtack up,â€ allowing additional layers to be applied and blended. Thicker applications may be worked for hours. This 6-color set includes: Hansa yellow opaque, Pyrrole red, quinacridone magenta, pthalo blue green shade, pthalo green blue shade and titanium white in 22ml tubes and an OPEN Application Guide.