Multi-layer steel OEM 2 Bolt Exhaust Gasket found on 300ZX, 350Z, FX35, G35, G37, & 370Z models.  2.25" inside diameter. 

These Nissan metal exhaust gaskets are reusable, unlike paper gaskets.

On 300ZX (Z32) models this gasket is found between the catalytic converter sections and the H-pipe and between the H-pipe and the muffler sections on the stock exhaust.  

Sold individually. 

On newer models these gaskets are used between the exit of the catalytic converters and the Y-pipe.

Z1 also offers a less expensive composite alternative available HERE.