3M1000NS-CART 10.1 Oz. Fire Barrier Water Tight Sealant (Pack of 1) by 3M

3M always makes quality products this is not cheap but worked great on the all metal smoke house I'm making from scrap metal parts. The bead holds well on horizontal surfaces. This caulk is extremely sticky so use disposal gloves. I used red oxide primer over the finished caulk and it seems to be adhearing, only time will tell.

I think to truly give this a review, I would have to burn the place down. Had to use this around a Laundry dryer vent that went through a fire wall in a Mixed use building as per inspectors request. Long story short, don't let your Hvac / venting guys run a dryer vent through a fire wall or fire blocking.

Had a project that required a fair bit of fire caulk. Tried a few tubes individually first. They seemed fine. Ordered a case. Had to return because they were old and had degraded in the tubes. When its nearly $11 a tube, and the caulk blows up in the tube, (and causes a mess in your gun) it's a problem.Amazon stepped up, took back my partially used case, and replaced the case in it's entirety. The new case was just fine, a good product, a good value.Without the need for the return, it would have been a strong 4 stars.

Bought it for hubby, he said it worked fine.

Have been using this product for long time. This is best used for roofing area where a kitchen exhaust duct or dryer exhaust duct penetrations require watertight sealing with fire rating.