| 454 / | HD | VENTILATION |
| 254 | DF | HAVING INLET AIRWAY {11} |
| 284 | DF | .~ Including specific air distributor (e.g., register, etc.) {14} |
| 309 | DF | .~.~ Louvered air distributor {3} |
| 313 | ![]() | .~.~.~ Moveable {5} |
| 314 | DF | .~.~.~.~> Aligned mutiple, movable sets of vanes {1} |
| 316 | DF | .~.~.~.~> Repositionable set |
| 317 | DF | .~.~.~.~> Rotating disks |
| 318 | DF | .~.~.~.~> Louver vanes form valve |
| 319 | DF | .~.~.~.~> Plural vanes pivoting about individual axes {1} |