| 277 / | HD | SEAL FOR A JOINT OR JUNCTURE |
| 345 | DF | SEAL BETWEEN RELATIVELY MOVABLE PARTS (I.E., DYNAMIC SEAL) {10} |
| 434 | DF | .~ Piston ring or piston ring expander or seat therefor {15} |
| 449 | DF | .~.~ Particular piston seat {6} |
| 452 | DF | .~.~.~ Oblique wall {1} |
| 453 | | .~.~.~.~ More than one oblique wall {1} |
| 454 | DF | .~.~.~.~.~> Having parallel walls |