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๐ค Seal it, save it, style itโFlex Black Paste gets the job done with flair!
Flex Seal Flex Black Paste is a 1lb jar of premium rubberized paste designed for quick, durable waterproof repairs on a variety of surfaces including metal, wood, glass, and PVC. Its unique formula creates a flexible, weather-resistant seal that prevents leaks and withstands seasonal expansion and contraction. The included 3-pack of professional putty knives ensures smooth, customizable applicationโperfect for both functional fixes and artistic textures. Trusted by DIYers to save time and money on home and vehicle repairs.
| ASIN | B08ML9943C |
| Best Sellers Rank | #303,367 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #282 in Putty Knives |
| Brand Name | Flex Seal |
| Color | Black |
| Compatible Material | Aluminum, Ceramic, Glass, Metal, Polyvinyl Chloride, Wood |
| Customer Reviews | 3.9 3.9 out of 5 stars (892) |
| Item Dimensions | 8 x 6.1 x 4.7 inches |
| Item Form | Paste |
| Item Weight | 1.1 Pounds |
| Manufacturer | Flex Seal |
| Material Type | Rubber |
| Part Number | PFSBLKR16 |
| Unit Count | 16 Ounce |
| Water Resistance Level | Waterproof |
M**E
Fixed Leak in Poured Basement Foundation
So I had 2 cracks running down my poured basement wall that would leak every time it rained. I was quoted $1000 to have someone come out and fix the leaks. SO, I went to the internet to see how to patch the leaks. You had to take a hammer drill and put holes 1 foot apart along the crack, paste these plastic tubes over each hole, put a paste over the crack that does NOT fill it in. Then inject a compound into the tubes that is supposed to fill in the cracks forever and survive the change in the seasons with the expansion and contraction. The kit would have cost me $250. So, I bought this, spent 10 minutes spreading it over the crack, I have had NO leaks for the last 3 months. Michigan has had more rain this summer than any I can imagine and my basement has been completely dry ever since. I have NOT gone through a winter yet so I do not know if that will affect the seal. I will try to post next summer to let everyone know if it held. SAVED A TON OF MONEY! EASY FIX! Picture doesn't show much, just wanted my review to get attention because I cannot believe how much it would have cost me to have professionals come out and do it. If you don't believe me, look up the process for sealing cracked basement walls. Update...it is now just over 2 years later...still no leaks. Works great.
A**S
Great stuff!
Our lawnmower is only a year old and somehow ended up with a couple of holes in the gas tank area when we uncovered it this spring. We used this paste and repaired the tank and the mower works perfectly fine again. You do need to make sure you reseal the container properly or the product will all completely dry out. The only disappointment was that it was not sealed the best from the manufacturer originally and most of the outer edge of the paste is unusable because it arrived dried out. We could only use the middle of the container upon opening a brand new product.
B**.
It fixed my leaking tank.
I had a leak in a tank on my humidifier. It is no longer manufactured so it could not be replaced. I tried another brand of glue but the leak was on a bend at the corner that was also tapered down at 45 degrees. The glue would not stay in place. I tried gorilla tape which I am sure would have worked but I could not get it to lie flat due to the bend and the angle. Then I ordered the flex paste. It was thick enough to stay in place on it's own. I was able to press it down into the small hole and spread some extra around the leak site for support. I then let it cure for 48 hours and success the tank is as good as new. However, the repair is not very pretty due to all the ribs on the tank and I was afraid to do too much cleanup because I did not want to damage my repair. So overall I am pleased. 1 It was easy to spread. 2 It was not the easiest to use in my case because it was messy. 3 It was waterproof and fixed my tank and that is all I really wanted. So overall I am very satisfied.
A**S
Cheap plastic container result in Paste hardening after only a few uses
The Flex Paste is sold in a Cheap plastic container that result in the Paste hardening after only a few uses. Flex Seal Liquid is sold in a metal can that is airtight, like Paint Containers, so its content does not harden. In my case, 98% of the Flex Paste harden and became non-usable because the Paste is not sold in an Airtight container. Spend your money on something else. Good only if you can use all of the Flex Paste immediately after opening.
A**.
Definitely Recommend for Water Leaks
This is fantastic stuff! Works great. Used it to seal a basement window well. Water was leaking into my house from the window due to a gap between the metal well & the soil but used this to seal it up & it never leaked again. It's been a few yrs now & it's still holding up.
J**F
Good product I assume if new.
The product had a 1/4 container harden and not usable. What was left worked well.
H**S
This is the Best Stiff!
Youโve seen the commercials. This stuff really works! My kids blew up my paddle board too much. ๐. I tried traditional SUP fixes but nothing worked. I bought Flex Steel and it came with the plastic spatula which was the perfect size. It was easy enough to use but the best part is that I have my loved SUP board back! ๐
A**R
Seals cracks and water proof
Product works , seals, and water proof.
Trustpilot
3 weeks ago
2 weeks ago