Here, you are looking at the Subaru OEM Turbo to Downpipe Gasket. This particular gasket endures more heat than most other gaskets on the engine, and it can become brittle after prolonged use. If you are performing maintenance that requires the removal of your downpipe, then you should thoroughly inspect this gasket for any damage. And although they are made from durable materials, they can become brittle over time, mileage, and extensive repetitive heat cycles.
Subaru Turbo to Downpipe Gasket: This gasket connects the back of the turbo to the downpipe manifold on your WRX, STi.