Advantages QuickMix™ Thin Plaster+ (386) is specially formulated to be used as the undercoat for all types of block walls. It is also suitable to be used as the spatterdash coat on concrete surfaces. Hardened QuickMix™ Thin Plaster+ surface can be further smoothened with Skim Coat - Base and Finish Coat. QuickMix™ Thin Plaster+ is suitable for interior and exterior use, however, it SHOULD NOT BE USED ON PAINTED SURFACES.