Frost King Thermal Well Products introduces this caulk saver that effectively fills gaps and openings. Frost King poly foam Reduces the amount of caulk you need to fill or seal large openings. Made of durable, resilient poly foam, Frost King caulk saver works with virtually every type of caulk and sealant. Moisture-repellent, this sealant caulk will never fall once fixed. Frost King polyfoam caulk saver works well with almost all caulk and saves on expensive caulk. The polyfoam sealant is 5/8 inches in diameter and 20-foot in length.