Sealant Tapes, Sprays, Paste, and Liquids


Flex Seal Family of Products (Swift Response, LLC)

Verify ID:


Expiration date:

July 12, 2022 - November 30, 2024

Verification Mark

Product Information

Flex Seal® Spray Flood Protection and Flex Seal Liquid® Flood Protection are both part of The Flex Seal Family of Flood Protection Products—an innovative line of products specifically designed to work together to create multiple layers of super-strong waterproof protection that can help seal out floodwaters and be easily removed after water recedes.
Flex Seal® Spray Flood Protection
This thick liquid spray seeps into gaps, cracks, and holes, and then dries to a watertight, removable, rubberized coating—sealing out water, air, and moisture. It is able to coat hard-to-reach areas and seal small openings that may not be visible. 
Flex Seal® Spray Flood Protection and is exceptional for sealing: small openings, seams, joints, windowsills, door jams, corners, and more. 
Flex Seal Liquid® Flood Protection
It starts out as a liquid and dries to a watertight, rubberized coating—sealing out water, air and moisture. It can be brushed, rolled or poured into areas that need to be sealed and is self-leveling, so gravity will pull it into hard-to-reach areas. Also, it can be applied directly over our other flood protection products as a final layer of protection to help seal openings that may not be visible.
Flex Seal Liquid® Flood Protection and is excellent for sealing: door thresholds, sliding door tracks, windowsills, door jams, casings, corners, and more. 

* This information was provided by Flex Seal Family of Products (Swift Response, LLC) and may contain additional information outside the scope of this Claim Verification.

Applicable To:

Flex Seal® Flood Protection Spray, Flex Seal Liquid® Flood Protection

Marketing Claim Verified by UL Solutions

No Water Penetration through 1/8” gaps at depths up to 3 feet, for 14 days

Verification Method

Products were applied to “L” shaped gaps to simulate a corner gap. Each “L” shaped gap had an 18” vertical and a 10” horizontal long gap. 1/8” gap widths were tested on a painted substrate. A fixture capable of holding 36” inches of simulated flood water from the bottom edge of each “L” shaped gap was used for the testing. The testing was conducted for 14 days while monitoring for leaks. All products were applied per the manufacturer’s instructions.

About the Company

Swift Response, AKA the Flex Seal® Family of Products, is an industry leader in providing a variety of DIY home repair, maintenance, and flood protection products with an emphasis on waterproofing, adhesive, bonding and sealing. To find out more visit

What is UL Verification?

UL Verification is an objective, science-based assessment that confirms the accuracy of marketing claims. Our independent assessment process scrutinizes the validity of specific advertising or promotional statements, giving you a way to separate verified fact from fiction.