| 440 / | HD | MARINE PROPULSION |
| 49 | DF | SCREW PROPELLER {12} |
| 53 | DF | .~ With means effecting or facilitating movement of propulsion unit or a segment of the propulsion unit (e.g., tilting or steering) {9} |
| 55 | ![]() | .~.~ Having restraining means {1} |
| 56 | DF | .~.~.~> With releasing means when propulsion unit hits obstruction |