81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube

Works great. My badly made NEW rear catalytic converter with a warped flange was leaking and it was giving me a code. Tried several time with different gaskets, but ended up using this silicone and a donut gasket/ Haven't got a code since. Good stuff.

If you're working on anything high-heat, like an exhaust manifold or turbo application, this is the only gasket maker to use. The Ultra Copper RTV is a workhorse—it handles maximum temperatures without breaking down, shrinking, or leaking. It goes on smoothly, cures quickly, and forms a super durable, tight seal. I've used it on headers where standard RTV would just burn up, and this holds strong. It's the professional choice for reliability under extreme heat. Essential for engine work.

The installation of the exhaust manifold went well! Time will tell if the repair holds or not.

Sealed my exhaust flange gaskets making it a better and tighter fit worth no leaks.

Good products.

Works right do I use this for valve cover gasket on small engines?

i use it to hold down the SCAT tubing thread. color matches perfectly

Didn’t actually use it but boy it is a nice package. Really I had some left from previous purchase that has ease of use & the color is the proper size & the flexibility of the adhesion make the entire job go as good as it should be and it doesn’t leak & it won’t come off of your skin if you let it dry as told by a professional stylist for the up and coming hair styles of the modern youth in and about any metropolitan areas where you may experience it for yourself.

Este sellador de silicona de alta temperatura ha funcionado de manera excelente en las uniones del escape de mi motocicleta. Su resistencia al calor extremo garantiza un sellado duradero sin deteriorarse con el tiempo. La aplicación es sencilla y la adherencia es muy buena, asegurando que no haya fugas ni vibraciones molestas en las conexiones. Además, su formulación a base de cobre proporciona una excelente conductividad térmica y estabilidad en condiciones exigentes. En general, un producto confiable y altamente recomendable para sellar uniones expuestas a altas temperaturas, como sistemas de escape y componentes de motor. ¡Gran desempeño!

Sehr gutes Produkt.

Five stars for a tube of sealant that appears to understand its role in life perfectly: go where it’s put, stay there, and stop important things from leaking out. Permatex Ultra Copper is excellent stuff. It applies well, spreads nicely, and gives you that reassuring sense that you are using a product designed by people who have met an engine and bear it no ill will. I used it for a gasket job where you very much want reliability over theatrics, and it behaved impeccably. What I liked most was that it felt properly substantial and easy to work with. Not too runny, not awkward, and it set up well. Once cured, it gave a solid, dependable seal and inspired far more confidence than some cheaper alternatives that seem to regard sealing as more of a philosophical suggestion. It’s the sort of thing you keep in the toolbox because sooner or later something hot, mechanical, and faintly temperamental will require attention. When that moment comes, this is exactly the kind of product you want on your side. Very good quality, does the job properly, and well worth having around

Product works very well, let is harden for at least 24 hours ! Exhaust leak resolved.. A+

良かったです