| 33 / | HD | GEOMETRICAL INSTRUMENTS |
| 300 | DF | INDICATOR OF DIRECTION OF FORCE TRAVERSING NATURAL MEDIA {23} |
| 355 R | DF | .~ Magnetic field responsive {6} |
| 363 R | ![]() | .~.~ Electrical telemetering {5} |
| 363 K | DF | .~.~.~> Photoelectric pickoff |
| 363 L | DF | .~.~.~> Electrical contact pickoff |
| 363 N | DF | .~.~.~> Electrolytic liquid pickoff |
| 363 Q | DF | .~.~.~> Resistance, capacitance, or inductance pickoff |
| 363 Y | DF | .~.~.~> Fluid jet or pressure pickoff |