The exhaust joint gasket will need to be replaced every time the exhaust system is removed and installed. (*It may cause exhaust leaks.) This prevents exhaust leaks at the connection between the exhaust pipe and the silencer, etc. so that it can perform at its full potential. The exhaust joint gasket is a non-reusable part, as it will be crushed during installation, so please make sure to replace it with a new one to prevent exhaust leaks.