I have a Hirth 280r i picked up that is an aviation application. It's a single plug, the tag says 280r13E. It has a pto prop adapter, factory free air cooling, it has an aluminum deflector that bolts on the head bolt extensions (yes all of them) the flywheel has no provision for a recoil cup or point adjustment window. There were no external ignition components included. It was free so I figure I'm ahead of the game if I can salvage any parts from the top end.