Zinsser B-I-N is the ultimate shellac-based primer, sealer, and stain killer, perfect for interior surfaces and spot priming of exterior surfaces. It offers unparalleled adhesion to glossy surfaces without scuff sanding and effectively blocks stubborn stains and persistent odours from smoke, fire damage, pets, and more. This primer seals porous surfaces with excellent enamel holdout, including bleeding knots and sap streaks. It works brilliantly on water stains, mildew stains, oil stains, marker pen stains, and many others. The dried film is non-toxic and hypo-allergenic, suitable for areas with incidental food contact. It is ideal for interior ceilings, walls, doors, and related paintable surfaces, as well as spot priming on exterior metal, trims, PVC, and wood. Key features include ultimate performance, permanent odour blocking, unparalleled adhesion to any surface without sanding, suitability for interior and spot exterior use, sealing of knots and sap streaks, drying in 15 minutes, and being recoatable in 45 minutes. Coverage is 12.5m² per litre.