Those of you with axle backs, did you re-use the OEM donut gasket?

I have the Invidia Q300 and it came with two donut gaskets but also these 2 metal rings.
Where do the metal rings go?

Thanks in advance!

 

I think this thread covers the same topic, seems like you should be able to re-use the stock donut gasket.

https://www.clublexus.com/forums/is-...t-exhaust.html

 

Yeah I stumbled upon that thread as well, I was just trying to rule out any leaks for the fuel issue that I'm having.