| 968 / | HD | HOROLOGY |
| 748 | DD | MEASURING, COUNTING, CALIBRATING, TESTING, OR REGULATING APPARATUS (measuring devices and calibers in general G01B; counters in general H03K) [G04D 7/00] {11} |
| 750 | | .~ Electrical measuring and testing apparatus [G04D 7/00C] {1} |
| 751 | DD | .~.~> For electric or electronic clocks [G04D 7/00C2] |