MIL-DTL-38999 Series III is the most widely used military circular connector with a triple-start threaded coupling for fast mating. Used in aircraft, missiles, ground vehicles, and shipboard electronics requiring high reliability.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | Pin A | Signal or power contact A | I/O |
| 2 | Pin B | Signal or power contact B | I/O |
| 3 | Pin C | Signal contact C | I/O |
| 4 | GND | Ground contact | GND |