6 inch Mercruiser exhaust extension.
 

Looking for one 6 inch extension, goes from manifold to elbow. Thank you.

Which riser joint?

Wet joint or dry joint??

It's a wet joint that bolts directly to the top of the manifold & the actual elbow bolts to the top of the extension. Found them new but I'm sure someone has one laying around that they took off.
Hope this helps.