Backer Rod is a closed cell, resilient, polyethylene backer rod used as a backup material for construction joints and applications that require sealants. It performs as a depth control for most known cold applied sealants. Sealants will not adhere to it; no bond breaker is required. COMPOSITION AND MATERIALS Backer Rod is a round, resilient, extruded closed cell polyethylene foam with a water resistant outer skin. It is compatible with most known cold applied sealants such as urethane, silicone, acrylic, butyl, polysulfides, latex, and chinking 6 lengths @ 72” long (3” diameter)
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