| Pin | Name | Description |
| 1 | Chassis ground | Lunchbox chassis |
| 2 | Output +4dB Hot | Output XLR pin 2 |
| 3 | Output -2dB Hot | Low level output (not used) |
| 4 | Output +4dB Cold | Output XLR pin3 |
| 5 | Analog ground | Input and output XLR pin 1 |
| 6 | Stereo link | Connects the side chains of 2 adjacent compressors |
| 7 | Input -2dB cold | Low level input cold (not used) |
| 8 | Input +4dB cold | Input XLR pin 3 |
| 9 | Input -2dB Hot | Low level input hot (not used) |
| 10 | Input +4dB Hot | Input XLR pin 2 |
| 11 | Gain Adjust | Buss feed on Radial lunchboxes |
| 12 | +16VDC | Positive power supply |
| 13 | Power ground | Connected to the Analog ground in the lunchbox |
| 14 | -16VDC | Negative power supply |
| 15 | +48VDC Phantom | Microphone phantom power supply |