The Cummins/Onan GGHH is a NG, LP generator set powered by a Ford V-10 6.8L engine. It is available at 12 V, 50 Hz. It holds about 5.5 L (1.5 gal) of oil. Starting uses 1 group-31 battery at 12 V.
Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.