Quick muffler question.

[littleblazer]

Just curious, I did a quick search and was looking through my manual and couldn't get a clear answer. Where the muffler connects to the catalytic converter, is that just a ball used to seal the muffler to the flange or is it actually a doughnut that needs to be replaced? I am assuming a doughnut since there is one listed but there doesn't appear to be an oem part number.

Thanks in advance.

 

[Mathoran]

My 2005 Envoy is all ball/sockets the only donut that I know of is the one between the exhaust manifold and catalytic.