| 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} |
| 457 | | .~.~ Using more than one pendulum (synchronization between master and slave pendulums subclass 532) [G04C 3/02K] |