0155-3261-02 Exhaust Elbow. Used on the Cummins Onan MDK range of Marine Diesel Generators with a wet exhaust system.
If you are replacing the elbow you will also need a new gasket. For MDKDK generators use 0185-6925, for MDKDL/MDKDM/MDKDN use A028X874.
This is a genuine Cummins part.