Backer Rods Are Used Before Caulking To Fill Gaps And Openings.
Backer Rods are made of nonabsorbent, closed-cell polyethylene pre-caulking material for long lasting durability and dependability. Acts as filler in large gaps before applying caulk. Insulates and cushions. Prevents 3-point bonding. Use in pavement cracks, wall joints and foundations. Types are Backer Rod For Gaps/Joints and Backer Rod Pro Pack. Sizes are 3/8 in., 1/2 in. and 5/8 in.. Lengths are 20 ft., 150 ft. , 250 ft. and 350 ft.. Color finish is Gray