Flex Seal Liquid

Liquid rubber you can brush, roll, dip, or pour.

6,200+ five star reviews*
Size: MAX - 2.5 Gal
Color: Black



Flex Seal Liquid seals out air, water, and moisture, and is mildew, chemical, and UV resistant. Available in Black, White, Clear, and Gray.

• Concrete and asphalt repair

• Foundation repair

• Prevent basement seepage

• Weatherize and seal out moisture

• Home and roof repair

• RV and motorhome weatherizing and repair

• Pools and pool equipment

• Outdoor fountains, bird baths, and more

Works on: Concrete, glass, brick, stucco, masonry, wood, copper, plastic, tile, fabrics, wires, vinyl, fiberglass, ceramic, porcelain, metal, aluminum, natural stones, foam, asphalt, EIFS, TPO, PVC, EPDM, CSPE, Hypalon polyurethanes and more.


Available in pints, quarts, gallons and new MAX 2.5 gallon container. Color options include black, white, clear and gray. MAX 2.5 gallon only available in black and white.

WARNING: California Proposition 65 Notice.

*Review count based on 5 star amazon.com reviews, collected between January 2016 and October 2023, and 5 star Bazaarvoice reviews from our retail partners, collected between March 2020 and October 2023.

33% savings based on price per oz, compared to our 16 oz size.


Protective clothing is recommended prior to starting any projects, make sure the surface is clean, dry and free of grease, oil and dirt. You can either brush, roll, dip or pour Flex Seal Liquid directly onto surface.

Increase adhesion by etching surface with sand paper.

Allow each coat to dry completely (24 to 48 hours) before adding additional coats. Flex Seal Liquid fully cures in 48 hours.

Tips for Brushing/Rolling Applications

Brush or roll Flex Seal Liquid using an even sweeping motion. Apply several even coats until the surface has been completely covered and ALL cracks and holes have been filled. Always brush or roll over a larger area than just where the leak occurred.

Tips for Dipping Applications

Dip object into Flex Seal Liquid, making a slight swirling motion. Once you feel the surface has been fully coated, remove and let any excess liquid drip back into the can. Hang or clip object in the same vertical position as it came out of the can and let dry.

Once fully cured, you will have a super strong, no slip, rubberized coating on the surface.

Tips for Pouring Applications

Pour Flex Seal Liquid directly on the surface, allowing gravity to take the liquid into cracks, holes, and/or other hard-to-reach areas.Continue to pour until the surface has been covered and all cracks and/or holes have been filled completely.

When pouring Flex Seal Liquid into an area of depth greater than ¼ inch, allow each ¼ inch layer to cure completely before pouring the next layer. Allow at least 48 hours for liquid to fully cure.

WARNING: Avoid contact with eyes and skin. Gloves and safety glasses are recommended. KEEP OUT OF REACH OF CHILDREN.