External Filler is a ready-to-use exterior graded filler based on special nano emulsion of 100% pure acrylic binder. It can be applied directly to most fair-face surfaces such as concrete, plasterboard walls and ceilings, brick or block work in exterior settings. When needed, it can be used for interiors as well. Once External Filler has been applied, it can be overcoated with a range of paint finishes.