QUICK-DRYING STAIN BLOCKER - A quick drying water based matt white Stain Blocker for interior and exterior use, with excellent adhesion to wood, plaster and previously painted surfaces. It will seal all stains that may bleed through and discolour paint. When dry, it can be painted with any type of paint and undercoat. Stain Blocker can be applied over asphalt, bitumen, crayon, creosote, graffiti, nicotine, rust, soot, tannin and water stains. Clean brushes in water.