As the original, shellac-base primer-sealer, nothing is better at permanently blocking stains, odours and wood knots than Zinsser B-I-N Primer.
For interior and spot exterior use.
Lightning fast dry - recoat in 45 minutes.
Seals knots and sap streaks.
Seals pet, smoke and musty odours.
Sticks to all interior surfaces without sanding.