This is a very high quality gasket made out of excellent material! My entire exhaust is 304 stainless steel, so having gaskets of the same material means that heating and cooling rates of the exhaust components are now equalized across components. This has led to the ability for the manifold studs/bolts to stay tight without constant need to get under the truck and tighten them every couple days. I installed these gaskets on a 1997 Toyota Land Cruiser FZJ80 with aftermarket exhaust. These fit perfectly on the flange face of the stock exhaust manifold (stock) to the Y-pipe/down pipe (aftermarket/custom). Very happy with my purchase from Grimmspeed!