Foam & Fill® Large Gaps & Cracks Expanding Polyurethane Sealant is quick and easy to use. It expands to fill holes, cracks, gaps, and voids around windows, doors, pipes, outlets, vents, and foundations. This insulating foam forms an airtight, waterproof bond and seals out drafts, moisture, and pests. Cured foam can be sanded, painted, or stained. Contains no HCFCs or CFCs so it is safe for the environment.