Zinsser Cover Stain Interior/Exterior Oil-Based Primer is designed to stick to any surface without sanding and can be used under and over oil and latex topcoats. This whole-house primer and sealer is a favorite with professionals, blocking stains, hiding dark colors, preventing tannin bleed, and penetrating exterior wood for a superior seal. Use it on ceilings, walls, doors, trim, cabinets, furniture, siding, fascia, soffits, foundations, railing, and more. Features Oil-based solution sticks to all surfaces and sands easily Designed for both interior and exterior applications High-hiding formula blocks most stains including those from water, smoke, and fire Sticks to glossy surfaces without scuff sanding Excellent for sealing water-soluble tannin bleed on cedar and redwood