| PartNumber | MS3451L40-9A | MS3451L40-1S | MS3451L40-1B |
| Description | Circular MIL Spec Connector RECEPT | Circular MIL Spec Connector RECEPT | Circular MIL Spec Connector RECEPT |
| Manufacturer | Amphenol | Amphenol | Amphenol |
| Product Category | Circular MIL Spec Connector | Circular MIL Spec Connector | Circular MIL Spec Connector |
| Number of Positions | 47 Position | 30 Position | 30 Position |
| Insert Arrangement | 40-9 | 40-1 | 40-1 |
| Contact Gender | Without Pin Contacts | Socket (Female) | Without Socket Contacts |
| MIL Type | MIL-DTL-5015 | MIL-DTL-5015 | MIL-DTL-5015 |
| Product | Receptacles | Receptacles | Receptacles |
| Shell Size | 40 | 40 | 40 |
| Shell Style | In-Line | In-Line | In-Line |
| Series | Matrix | Matrix | Matrix |
| Packaging | Bulk | Bulk | Bulk |
| Brand | Amphenol Aerospace | Amphenol Aerospace | Amphenol Aerospace |
| Shell Plating | Electroless Nickel | Electroless Nickel | Electroless Nickel |
| Mating Style | Threaded | Threaded | Threaded |
| Product Type | Circular MIL Spec Connector | Circular MIL Spec Connector | Circular MIL Spec Connector |
| Shell Material | Aluminum | Aluminum | Aluminum |
| Factory Pack Quantity | 1 | 1 | 1 |
| Subcategory | Circular Connectors | Circular Connectors | Circular Connectors |
| Part # Aliases | 3451L409A | 3451L401S | 3451L401B |