QUICK-DRYING PRIMER & UNDERCOAT – Rustin’s Quick Drying Primer and Undercoat is for use on interior and exterior work. Used as a primer, it is suitable for new and bare wood, MDF, plaster, brickwork and cement. It has high opacity and can be used as an undercoat on primed or painted surfaces. This paint may be over coated with water or solvent based finishing paints. Clean brushes in water.