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Flex Paste

Flex Paste, Waterproof Paintable Putty, Spackle Sealant, Fill Gaps Cracks Holes - Block Out Water and Air - UV Resistant - Walls, Drywall, EPDM, Concrete, Roof, RV Repairs, Black, MAX

  • Based on 6,061 reviews
Condition: New
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Availability: In Stock.
Fulfilled by MaxWarehouse
Arrives Sep 20 – Sep 21
Order within 5 hours and 58 minutes
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Color: Black


Size: MAX


Features

  • NEW! STAY FRESH CONTAINER Blocks out air and locks in freshness to extend the sealing power of Flex Paste, with no waste
  • COAT, SEAL & PROTECT - Penetrates deep to seal out air, water, and moisture. Once dry, it turns into a strong, flexible, watertight, rubberized barrier
  • WORKS UNDERWATER - Can be applied underwater, and it even dries underwater
  • FILLS LARGE AREAS - Super thick rubber paste clings to the surface and instantly fills large gaps, cracks, and holes
  • FULLY PAINTABLE - Once fully cured, it can be painted any color. Helps prevent rust and corrosion, and it is UV resistant
  • EXCELLENT FOR filling cracks and holes, foundation and concrete repairs, bath and shower, indoor and outdoor projects, roof, RV, motorhome, auto, marine, lawn and garden projects, DIY, hobbies, and more
  • MADE IN THE USA

Description

Penetrates deep to seal out air, water, and moisture. Once dry, it turns into a strong, flexible, watertight, rubberized barrier. Use on: Wood, glass, tile, concrete, aluminum, metal, brick, stucco, masonry, PVC and so much more. No need to wait for surfaces to completely dry before sealing them. It even cures underwater. This thick rubberized paste is exceptional for all types of crafts, hobbies, and more. Flex Paste stays completely flexible, making it perfect for all-season roof repairs and all types of DIY projects. Flex Paste is proudly made in America, using globally sourced products. Using putty knife, trowel or similar tool, remove an even layer from the top surface. Do not scoop deeply into the tub as this may create air pockets. Apply a generous amount to the surface using a smooth motion. Always make sure all cracks & holes have been completely filled & cured before testing.

Material: Rubber


Brand: Flex Paste


Style: 12 lb Black


Item Weight: 12 pounds


Item dimensions L x W x H: 7.75 x 6.75 x 6.75 inches


Brand Name: Flex Paste


UPC: 850017897472


Unit Count: 192 Ounce


Number of Items: 1


Included Components: Item


Item Type Name: Flex Paste MAX Black Joint Compound 12 Lbs -Case of 1


Manufacturer: Swift Response, LLC


Model: PFSMAXBLK01


Part Number: PFSMAXBLK01


Warranty Description: 1 Year Limited


Item Weight: 12 pounds


Item Dimensions: 7.75 x 6.75 x 6.75 inches


Water Resistance Level: Waterproof


Item Form: Paste


Compatible Material: Wood, Glass, Tile, Concrete, Aluminum, Metal, Brick, Stucco, Masonry, Copper, Fabric, Fiberglass, Ceramic, Porcelain, Natural Stones, Roofing, Pvc, Eifs, Cspe, Epdm, Hypalon Polyurethanes


Style Name: 12 lb Black


Color: Black


Surface Recommendation: Windows,Doors


Material Type: Rubber


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 20 – Sep 21

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews

    • Saved my Planter
Color: White Size: Half-Quart
Worked great to seal a beloved planter that was damaged by the weed eater. I don't have to worry about all of the dirt and water running out of it. Easy to apply and set up quickly.
Reviewed in the United States on July 29, 2026 by Nic
    • AWESOME PRODUCT TO PATCH AN EPDM FOUNTAIN LINER!!
Color: Black Size: Cartridge
This is the only product that I could find that I could use in a outdoor fountain that has a thick EPDM GoodYear made liner that would stick, and that was safe, out of all the other products on the market. Thank you
Reviewed in the United States on July 13, 2026 by John C.
    • Works well, but product arrived with dry layer on top
Color: Black Size: Half-Quart
Product worked very well. Good amount of workable time, spreads well with a small spackling knife. The only complaint is that the product arrived with the top 1/8" dried up and unusable, and since you don't get that much in the can, having to throw away about 2 spoons full is a real problem. They need to seal the can lid better. ... show more
Reviewed in the United States on March 5, 2025 by Edward
    • Dried up useless, no customer support
Color: Black Size: Half-Quart
Review Image by Mel
Review Image by Mel
Bought for a project, opened just after the Amazon return window and it was a dried up rock. Reached out to customer service with Flexseal and they never did anything. Make sure you check it before the return window, I was only a couple days late.
Reviewed in the United States on July 8, 2026 by Mel
    • It fills you up.
Color: White Size: Half-Quart
It does everything that they say. It is also very easy to work with.
Reviewed in the United States on August 2, 2026 by charles pillow
    • Ordered the "Stay Fresh" can, received the plastic tub
Color: White Size: Quart
Amazon's web page shows the "NEW! Stay Fresh Container", but they shipped the old obsolete plastic tub. As many of the other reviewers have correctly stated, the plastic tub cannot keep the product soft, pliable and usable. I called the FlexSeal factory, and they are fully aware of the problem. If you order from the FlexSeal website, the factory is shipping the Stay Fresh can as of 2024, March 12. This is a good product, but it's a complete waste of money to buy it in the obsolete plastic tub. That form of packaging is incapable of keeping the product in usable form. It hardens from the top down. I bought two from local stores, and learned that if you squeeze the tub at the top and it doesn't feel soft, the product has hardened and won't be usable. Typically it will be softer near the bottom, but all of the product above (the unsqueezable part) is so hard you can't get it onto the putty knife. Amazon needs to stop shipping the product in the obsolete plastic tub. Update: I called Amazon Customer Service and advised them that the plastic tub packaging is obsolete and no longer being shipped by the factory, and that they should return all product in the plastic tubs, and ship only the product (in the can) shown on the web page. I was advised that they would do so. That was on March 16, the same day I ordered the new (can) packaging directly from the factory. It arrives today (March 20). Shipping was free. Looking forward to seeing how it performs in patching a stucco parapet wall. Update: I received the can from the factory. The product was fresh and easy to apply. Because I was applying it on stucco, it took more to fill all the nooks and crannies than I expected, so I will need another can to finish the job. I ended up doing the whole job with a putty knife. I applied it in full sunlight on a warm breezy day, but it stayed flexible enough to work it into a smooth surface as I went. I doubt it will need a second coat. I don't know how long it will last, but I expect it will be pretty durable. There is no way any rain is going to get through the FlexPaste. I used a rubber spatula to scrape all the product from the sides and bottom of the can. Clean-up was easy; I just wiped the material off the tools with paper towels. ... show more
Reviewed in the United States on March 16, 2024 by Fezno Mint
    • Good purchase
Color: White Size: Half-Quart
This is great as long as you know its a one use product for whatever your project may be. You can't seal the container up adequately enough to prevent it from drying out. I would encourage you to purchase multiple small packages rather than one large one if you have multiple projects or just resign yourself to a lot of product loss. I personally used it to coat the ends of peg style towel holders so towels would stop slipping off the slick ends and into the floor. Worked, and I didn't have to remove old hardware and purchase new ones. That's a win. ... show more
Reviewed in the United States on June 17, 2026 by middleagediva
    • Great leak patching material
Color: Black Size: Half-Quart
Excellent for patching leaks in most stiff materials.
Reviewed in the United States on August 8, 2026 by RANDMART

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