Frost King 3/8 In. x 350 Ft. Poly Foam Backer Rod

Frost King's Poly Foam Backer Rod reduces the amount of caulk you need to fill large openings. It's non-absorbent. So, it works with virtually every type of caulk and sealant. It's also compressible which allows it to snuggly fill cavities. Just press in place, then caulk on top of it.

• Saves expensive caulk while filling large gaps
• Convenient, easy to carry contractor box
• Made from non-absorbent compressible material for optimal sealing
• Moisture repellent
• Works with virtually all caulks and sealants
• Fills gaps and openings to prevent drafts
• Provides a sound surface for caulking projects
• Easily trimmed to size with scissors
• Also referred to as backer rod