| EARPHONE CONTROLLING AGENCY | WESTERN ELECTRIC |
| EARPHONE ELEMENT TYPE | MAGNETIC |
| EARPHONE IDENTIFYING NUMBER | HC4 PART NO. |
| EARPHONE IMPEDANCE RATING | 600.0 OHMS NOMINAL |
| EARPHONE MOUNTING METHOD | SUSPENDED ON HEADBAND |
| EARPHONE QUANTITY | 1 |
| CONNECTOR CONTROLLING AGENCY | WESTERN ELECTRIC |
| CONNECTOR IDENTIFYING NUMBER | 289B PART NO. |
| CONNECTOR NAME | PLUG |
| CONNECTOR TO JUNCTION CORD LENGTH | 7.000 FEET |
| CONTROLLING AGENCY | WESTERN ELECTRIC |
| DC RESISTANCE RATING IN OHMS | 350.0 NOMINAL |
| FREQUENCY RATING | 0.2 KILOHERTZ MINIMUM AND 4.0 KILOHERTZ MAXIMUM |
| IDENTIFYING NUMBER | N1 PART NO. |
| MICROPHONE ELEMENT TYPE | CARBON |
| MICROPHONE MOUNTING FACILITY | ADAPTER FASTENED TO LEFT SIDE OF HEADBAND |
| OPERATING CURRENT RATING | 60.0 MILLIAMPERES NOMINAL |
| OUTPUT LEVEL RATING | 35 DB ABOVE 1 MV |