A solvent-based primer specially formulated to seal unstable areas which remain powdery and chalky after the surface has been thoroughly prepared for painting with Dulux Trade Weathershield Masonry Paints. Up to 12m² per litre on most surfaces. Application coverage: 12m² per litre. Touch dry: 8-12 hours dependent upon temperature / humidity. Recoatable: 16-24 hours. Thinning: This product should not be thinned. Key Benefits: Stabilises powdery masonry surfaces. Ready for use. Use only on dry exterior masonry that remains powdery and friable after thorough preparation. For best results, shake the can well before opening. Apply using a brush or roller to the powdery or chalky areas and allow to dry fully. If the area remains powdery or chalky once dry, apply a second coat to the applicable area. Please note this primer isn't general purpose and is only suitable for chalky or powdery areas. New surfaces should only ever be sealed with a thinned coat of the chosen masonry paint before applying two regular top coats (not thinned).