Looking for a "silver bullet" primer that covers everything? Choose the primer that contractors have kept in their vans for decades: Zinsser BIN Shellac-Base Primer. As the original shellac primer/sealer, nearly nothing is better at permanently covering bleeding wood knots, sap streaks and graffiti as well as water, grease, rust, smoke and many other types of stains. This pioneering primer/sealer permanently blocks most every kind of odor, too. When it comes to preparing indoor surfaces for topcoats while sealing nearly any porous surface, especially where excellent enamel holdout is required, few primers match BIN Shellac-Base Primer. It can even be applied when temperatures dip below freezing. Though it's designed specifically for indoor application to ceilings, walls, doors, trim, cabinets, furniture and more, this versatile product is also capable of spot priming certain exterior surfaces (see product packaging for more details). Paint Sub-Category: Primer, Shellac-Based; Intended Application Environment: Interior/Exterior; Finish/Sheen: Flat; Color(s): White.