how many feet come in a 3 pk?

Both INDIVIDUAL packs - the 3/8" and the 1/2"- are 20 feet long.

no 1/4" one? either 20 or 50ft?

Not in this brand, but Amazon offers 1/4-inch backer rod in various lengths, from 10 feet to 100 feet, from other brands. Just search on "Backer Rod 1/4 Inch".

can the backer rod be sliced for smaller openings?

I have not done that, but it cuts easily with a sharp knife or scissors, so you should be able to slice it to fit whatever opening you have. It's good stuff!

Can his be used for exterior windows before caulking?

I used it to push into larger cracks in my driveway before applying concrete filler, and it worked great. I'm thinking that it should work well for filling in spaces around your windows prior to caulking.

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

Help Track order

Account Cart

MD Building Foam Backer Rod, Gray, 3/8in x 20ft for Small Gaps

MD Building Foam Backer Rod, Gray, 3/8in x 20ft for Small Gaps

Product ID: 5587474

Details

Brand
M-D Building
Color
Gray
Item Form
Foam
Item Weight
17.01 g
Surface Recommendation

✂️Easily trims with scissors

🌧️Weather-resistant & waterproof

🛠️3/8in x 20ft perfect gap size

2658 kr

Duties & taxes included

In stock

Sold byAmazon IcelandDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Iceland.

Secure transaction

Description

🔧 Seal Smart, Save Big: The Pro’s Choice for Flawless Gaps!

CAULK WASTE REDUCTION - Creates a reliable base that prevents caulk overuse, saving money and ensuring a clean finish.
EFFORTLESS INSTALLATION - Push-in design fits most joints instantly—no adhesives or messy sealants required.
DURABLE WEATHERPROOF DESIGN - Crafted from closed-cell foam that resists moisture and harsh outdoor elements without degrading.
PRECISION FIT FOR SMALL GAPS - Snugly seals medium joints to block drafts, dust, and insects for year-round comfort.
VERSATILE INDOOR OUTDOOR USE - Ideal for driveways, window sills, doors, and roofs—your all-in-one gap sealing solution.

The MD Building Foam Backer Rod is a 3/8-inch by 20-foot closed-cell foam strip designed to fill and seal small to medium gaps indoors and outdoors. Its weather-resistant, waterproof rubber material ensures long-lasting durability while preventing drafts, moisture, dust, and insects. Easy to trim and install, it provides a sturdy base for caulking, reducing waste and enhancing adhesion for professional-grade sealing and insulation.

Specifications

ASIN	B000BQS90G
Best Sellers Rank	#2,540 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #1 in Rope Caulk #30 in Industrial Sealants #1,153 in Hardware
Brand	M-D Building Products
Brand Name	M-D Building Products
Color	Gray
Customer Reviews	4.6 out of 5 stars 1,666 Reviews
Global Trade Identification Number	00043374714647
Included Components	MD Building - 71464 - 2pk
Item Form	Foam
Item Highlight	Closed-Cell Foam, Prevents Caulk Waste, Cuts With Scissors, Blocks Drafts Moisture Dust Insects, Indoor/Outdoor
Item Type Name	MD Building - 71464 - 2pk
Item Weight	17.01 g
Manufacturer	M-D Building Products
Material Type	Rubber
Model	71464
Number of Items	1
Number of Packs	1
Part Number	71464
Surface Recommendation	surface_recommendation
UPC	043374714647
Unit Count	1 Count
Warranty Description	All M-D products are warranted to be free from defects in material and workmanship if installed and used in strict accordance with our installation instructions.
Water Resistance Level	Waterproof

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Meera L.

Smooth transaction and product arrived in perfect condition.

3 weeks ago

Anjali K.

The product quality is outstanding. Exactly what I needed for my work.

1 month ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.