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0.625-in x 20-ft Closed cell Backer Rod, Gray

Ratings & Reviews for M-D 0.625-in x 20-ft Closed cell Backer Rod, Gray

4.6
1238
Review
 4.6 out of 5
1238 Reviews


96% Recommend this product

Ratings may include incentivized customer reviews.

What Customers Are Saying

Customers overwhelmingly praise this backer rod for effectively preparing gaps before caulking, with most reporting it saves sealant, reduces mess, and creates durable, long-lasting seals around windows, doors, and flooring. Reviewers highlight its ease of use—easy to cut, compress into tight spaces, and hold in place through friction—making it versatile for driveway cracks, pool edges, and laminate perimeters. Many note it stops cold drafts and improves home insulation. Customers commend its quality and value, with strong loyalty evident. A few mention slightly smaller diameter than expected, but overall performance feedback is consistently positive.

Customer review summary generated by AI, including incentivized reviews.
1238 Customer Reviews

floating on top of grout

Would Not Recommend

If you use it on floor with self leveling compound it will float to the top in about 20 minutes waste of time and material

October 7, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray
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Working great

Would Recommend

Worked great around my screen door frame

October 6, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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ldom

Would Recommend

great to cover windows cracks

October 5, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Multiple uses

Would Recommend

Was able to use for sealing a gap on an exterior wall - snug and hopefully will stay and functional as intended

October 3, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Molding

Would Recommend

I bought this to use with my new flooring as stair nose molding. It is just what the Doctor ordered.

October 3, 2026
From 0.375-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Air Flow

Would Recommend

Helped our door from leaking air around it, worked exactly as advertised.

October 2, 2026
From 0.375-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Gap filler

Would Recommend

Great at filling in uneven gaps. Allowed me to have a good base for caulking.i would use again.

September 30, 2026
Verified Purchaser
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Great uneven gap filler

Would Recommend

This helped to fill in uneven gaps and allow me to get a good caulk line. I have used these gap fillers a few times and find them very versatile.

September 30, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Had some extra large openings, needed to fill voids, and covered with chalking grout. Looks GREAT!!!

September 28, 2026
From 0.375-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Would Recommend

Great filler for deeper expansion joints

September 28, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Would Recommend

The gray color shows through a light color caulk. Otherwise, it does fill the gap.

September 25, 2026
From 0.5-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Would Recommend

I found that the gray color shows through the white caulk.

September 25, 2026
From 0.375-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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Gap filler

Would Recommend

This worked great for a gap between sink and marble vanity.

September 25, 2026
From 0.375-in x 20-ft Closed cell Backer Rod, Gray Verified Purchaser
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