Zinsser B-I-N® Aqua is a high-performance white-pigmented low-odour water-based, synthetic shellac-based knot block primer and sealer combining fast drying times with unrivalled adhesion and best possible coverage. Seals: tannin, knots, sap streaks, cigar, cigarette & nicotine odours, severe water stains, fire & smoke damage, rust stains, graffiti, crayon, lipstick and grease.