Zinsser b i n white matt primer sealer 2500mlapply this primer sealer from zinsser to interior porous surfaces even bleeding knots sap streaks as well as water stains fungal degradation nicotine oil stains marker pen stains more using a brush or roller to prepare the surface for painting it seals primes blocks stains kills odours it takes 15minutes to dry and will cover up to 12 m per litre on average