| PartNumber | MS3101A20-4S | MS3101A20-4P-RES | MS3101A20-4P |
| Description | Circular MIL Spec Connector 4P #12 SKT CONTACTS | Circular MIL Spec Connector ER 4C 4#12 PIN RECP | Circular MIL Spec Connector 4P #12 PIN CONTACTS |
| Manufacturer | Amphenol | Amphenol | Amphenol |
| Product Category | Circular MIL Spec Connector | Circular MIL Spec Connector | Circular MIL Spec Connector |
| RoHS | N | - | N |
| Number of Positions | 4 Position | 4 Position | 4 Position |
| Insert Arrangement | 20-4 | 20-4 | 20-4 |
| Contact Gender | Socket (Female) | Pin (Male) | Pin (Male) |
| MIL Type | MIL-DTL-5015 | MIL-DTL-5015 | MIL-DTL-5015 |
| Product | Receptacles | Receptacles | Receptacles |
| Shell Size | 20 | 20 | 20 |
| Shell Style | In-Line | In-Line | In-Line |
| Series | MS 5015 | MS | MS 5015 |
| Brand | Amphenol Industrial | Amphenol Industrial | Amphenol Industrial |
| Shell Plating | Olive Drab Chromate over Cadmium | Olive Drab Chromate over Cadmium | Olive Drab Chromate over Cadmium |
| Product Type | Circular MIL Spec Connector | Circular MIL Spec Connector | Circular MIL Spec Connector |
| Factory Pack Quantity | 1 | 1 | 1 |
| Subcategory | Circular Connectors | Circular Connectors | Circular Connectors |
| Tradename | 5015 | - | 5015 |
| Part # Aliases | MS3101A20-04S MS31O1A20-04S MS31O1A20-4S U61-168120-04S | 39M5105 | 61-168120-04P MS3101A20-04P MS31O1A20-04P MS31O1A20-4P U61-168120-04P |
| Termination Style | - | - | Solder |
| Current Rating | - | - | 23 A |
| Qualification | - | - | EREL |