Enhance your window and door insulation with the M-D Building Products Caulk Saver Foam 1 in. x 10 ft. This gray foam backer rod is designed to fill large gaps and joints before applying caulk, helping to create a more effective seal and reduce drafts. The closed cell foam construction is waterproof and flexible, making it ideal for use as a backing rod for caulking around windows, doors, and walls. Its lightweight design—just 0.3 lb.—makes installation easy, while the 1 in. diameter fits most standard gaps. Use this foam caulk saver to improve the performance of your window caulk or wall caulk, minimize caulk consumption, and achieve a professional finish. Perfect for both interior and exterior projects, this foam caulking filler is compatible with most types of caulk, including acoustic caulk. Each package contains three foam rods, each measuring 10 ft. in length, providing ample material for multiple projects. No batteries required. Trust M-D Building Products for reliable, long-lasting results in your home improvement projects.