The PEF Closed Cell Backer Rod, made from high-quality closed-cell polyethylene foam, provides a firm, consistent base for elastomeric sealants. Ideal for vertical and horizontal joints, it’s perfect for precast concrete panels, brick and masonry expansion joints, saw-cut concrete floors, tiled surfaces, penetrations, and window or door perimeters. It can also serve as a draught or dust seal where sealant is not required.