| 174 / | HD | ELECTRICITY: CONDUCTORS AND INSULATORS | 
| 68.1 | DF | CONDUITS, CABLES OR CONDUCTORS {15} | 
| 70 R | DF | .~ Combined {8} | 
| 74 R | DF | .~.~ With end structure {10} | 
| 75 R |  | .~.~.~ With joint {4} | 
| 75 B | DF | .~.~.~.~> Bootleg | 
| 75 D | DF | .~.~.~.~> With detachable joint (e.g., potheads) | 
| 75 F | DF | .~.~.~.~> Flexible spring type | 
| 75 C | DF | .~.~.~.~> Coaxial |