| 123 / | HD | INTERNAL-COMBUSTION ENGINES |
| 41.01 | DF | COOLING {27} |
| 41.56 | DF | .~ Air-cooled {7} |
| 41.6 | ![]() | .~.~ Steam dividing vanes, baffles, conduits, or the like for multiple cylinders {2} |
| 41.61 | DF | .~.~.~> Individual deflecting cylinder baffles |
| 41.62 | DF | .~.~.~> Air duct with discharge ports or conduits |