Backer rod is an ideal non-absorbent compressible backup material inserted into a joint to control sealant depth. This creates a backstop to allow proper sealant tooling, and proper sealant of the joint surfaces. Backer rod can also be used as a temporary joint seal.
Fills large gaps and openings to prevent drafts
Easily trimmed to size with scissors
Provides a sound surface for caulking projects
For use in expansion joints in driveways and sidewalks
Sold in 100-feet rolls