Owatrol Primall is a fast drying interior primer for the blocking of unknown stains and the priming of difficult surfaces. When used on porous surfaces, Primall will help to stabilise the surface and prevent shadowing on the finish coat. When used on smooth surfaces, Primall is ready to use without the need to sand, and can even be applied over lightly rusted surfaces as an anti-corrosion primer. It also improves the performance of the finish and makes applying the finish easier.