M-d - Polyethylene - Caulk Backer Rod - For Driveways And Sidewalks - Large - Gray - 20 Ft.

This Gray Backer Rod is designed to fill gaps and joints before caulking, reducing the amount of sealant needed. Made from closed-cell polyethylene foam, it resists moisture and drafts, enhancing energy efficiency. Flexible and easy to cut, the backer rod conforms to irregular joint shapes that provides a sound surface for caulking in both indoor and outdoor applications.