Pettit Paint ProPoxy Two Part Epoxy Primer Gray Gallon Kit. Primes and seals properly prepared substrates. Features excellent sanding qualities and enhances the high gloss finish of ProPoxy topcoat. Used for both interior and exterior applications to seal undercoats and fillers. Non-porous primer provides superior adhesion, chemical and corrosion resistance to a variety of substrates including fiberglass/gelcoat, wood, properly etched/primed metal, and previously painted 2-Part paint surfaces. Kit includes 1 gallon base and 1 gallon catalyst.