Transparent Extender is the binder base for all Auto Air Colors except for 4100 Series and 4200 Series Detail and Semi-Opaque Colors. Transparent Extender may be added to colors to increase transparency, allowing colors to have lighter values. Add in small increments. May be added up to 25% of the mixture, after that the colors tend to wash out as the pigment load is spread out. Not to be used with Auto Air 4200 Series Detail Colors.