| 968 / | HD | HOROLOGY |
| 446 | DD | ELECTROMECHANICAL CLOCKS OR WATCHES INDEPENDENT OF OTHER TIMEPIECES AND IN WHICH THE MOVEMENT IS MAINTAINED BY ELECTRIC MEANS (synchronization subclass 506) [G04C 3/00] {8} |
| 453 | DD | .~ Wherein movement is regulated by a pendulum [G04C 3/02] {5} |
| 454 | DD | .~.~ Using mechanical coupling (using more than one pendulum subclass 457; using torsion pendulums subclass 464; using conical pendulums subclass 465) [G04C 3/02B] {1} |
| 455 | | .~.~.~ With constant impulses [G04C 3/02B2] |