174 / | HD | ELECTRICITY: CONDUCTORS AND INSULATORS |
8 | DF | WITH FLUIDS OR VACUUM {12} |
24 | ![]() | .~ Conduits, cables and conductors {3} |
25 R | DF | .~.~> Impregnated insulation type {4} |
27 | DF | .~.~> Parallel or twisted conductors |
28 | DF | .~.~> Coaxial or concentric type {1} |