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BSG
2025-09-03 10:52:26
I've been using 3M fire barrier for 30 plus years. As a requirement under the National Fire Protection Association, it is a requirement when running telecommunications cables through firewalls. Every now and then, I pick up a project that requires me to use this. It is most always readily available, and the price is competitive with other manufacturers. It is also moldable to any form. In my opinion, this is the best fire barrier on the market.
Trafalgar
2025-08-23 12:20:08
I bought this to fireblock a short 2-foot conduit I ran from the electrical panels in my garage through the rim joist into the basement to carry a bunch of yellow 12 gauge Romex wire. The inspector didn't care if I fireblocked it or not but I did, as I also want to keep bugs from using the conduit as a superhighway and I try to keep my house as tightly air-sealed as possible.This stuff was easily moldable and mashable and did the job with no problem. I sealed the conduit from both ends for good measure. I have a bit leftover from the job that should keep for a long time in the original tube.
NH Guy
2025-08-08 12:30:26
You can't beat the standard for fast application, but I really like this moldable putty for small jobs, and jobs you may have to pull the plug out, install another cable, and stuff it back in. I don't have to try and keep a tube of caulk from drying out, I don't get red caulk all over everything, and the putty is stiff enough to plug the sloppiest hole. I always keep one in the tool box. Just pinch off as much as you need and stuff it in the hole, great for remodel jobs.
Keith
2025-08-01 17:46:19
The pictures are deceptive. I was comparing with others and they weren't consistent. One was in fluid ounces another in pounds. I should have known. Not a horrible price but now I have to order another tube.
Lance Walker
2025-07-31 11:22:01
I needed something to block openings around the electrical boxes for lights and smoke detectors in my ceiling, and this is a much better option than only using caulk (at least in areas where the red color doesn't show). I'm impressed with how easy it is to mold into the right shape with its putty consistency - as well as its ability to be stuffed into odd shaped openings. The fire retardant capability is a great plus
Customer
2025-07-22 15:56:47
So far, nothing to dislike. Hopefully, I will never have to test thr levrl of fire protection. Easy yo work with. A must have when running wires through walls in vehicles and RVs.
WilBro
2025-03-19 11:08:10
Awesome stuff, I'm using it to fill gaps in soundproofing applications, and in running conduit for air-lines for a compressor. Easy to work, removes and can be reused if not contaminated by plaster or wood dust. Also not crazy expensive, given that it comes from the 3M company, one manufacturer who seems to have maintained quality in this age of atrociously bad quality for cheap consumer goods. Thumbs up!
kokomo
2025-02-27 11:33:59
This was just what I needed to seal a hole after removing a wire from an electrical box.Soft and easy to use. Not sticky, having a clay consistency.
Steve
2025-02-11 14:20:38
I use this for blocking holes in engine firewalls. It molds easily around cables and wires and sticks well to block the holes. I have not checked its fire resistance. After a year it is still flexible and stuck in place. Does the job of blocking fumes from making their way out of the engine compartment.
Shopper
2025-01-01 16:31:41
Very workable and hopefully flame proof putty. Easy to work with and good to put a temporary seal around air drafts.
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