The D38999 20FF11PCN represents the pinnacle of rugged circular connector technology, designed explicitly for the most demanding military and aerospace applications. As part of the MIL-DTL-38999 Series unparalleled reliability in extreme conditions. Its design prioritizes robustness, environmental sealing, and consistent electrical performance—critical factors where failure is not an option.
This connector is mission-critical across sectors where performance under duress is non-negotiable:
As a direct manufacturer of military-grade circular connectors, we eliminate middleman markups to provide competitive volume pricing for aerospace and defense procurement. Every connector undergoes rigorous environmental sealing and high-vibration testing to ensure strict compliance with international military standards, effectively lowering your long-term maintenance costs. We support flexible MOQs and stable global delivery to keep your supply chain on schedule. 
| Series | MIL-DTL-38999 Series III |
| Coupling | Triple-start threaded coupling |
| Shell material | Corrosion-resistant aluminium alloy |
| Shell finish | Cadmium plating |
| Contact material | Copper alloy, gold plated over nickel |
| Contact type | Type J (standard power and signal) |
| Contact density | High density insert |
| Signal current | Up to 5 A per contact |
| Power current | Up to 23 A per contact |
| Voltage rating | 1,500 V AC RMS |
If you’re buying for a defense or aerospace program, you arrive with a drawing that already carries a part number and need the shell to match it exactly. If you design cable assemblies, you need the same model to close out a high-density build in fixed panel space. If you run an MRO or repair station, you order small quantities as drop-in replacements for worn shells, often against a repair deadline. If you’re a distributor, you stock it for repeat demand.
Every one of you wants the same thing: a mating half that fits the first time. As the MIL-DTL-38999 manufacturer, we build and inspect every unit on our own line, so one source covers first sample through repeat order.
The shell is rated from -65 °C to +200 °C and sealed to IP67/IP68 against moisture ingress, with salt fog and chemical exposure covered as well. That is what a harsh environment connector means in practice: it can sit in an engine bay, on a deck or on a vehicle chassis without losing contact integrity. Match the rating against your program's environmental test plan before you specify.
Yes. The insert can be specified as a hybrid arrangement carrying signal, power, coaxial and high-speed data contacts inside the same D38999 connector, which is useful when a panel has run out of room for separate shells. The arrangement has to be fixed before the connector is built, so confirm the contact mix your cable assembly needs when you settle the part.
Yes — the shell follows the standard Series III mating dimensions, so plugs and receptacles already in service mate with it. What has to line up is the shell size, insert arrangement, contact type and keying, all of which the part number encodes. As a MIL-DTL-38999 manufacturer we can confirm the mating half for your number.
Keep the dust cap on whenever the connector is unmated, and store spare units in their packaging rather than on a damp floor. Wipe the shell with a damp cloth instead of a solvent when salt or dust builds up. Before mating, check the insert for grit and look over the coupling thread and the interfacial seal, because grit trapped in the seal is the usual cause of moisture trouble later.
Series III covers a range of shell sizes and insert arrangements, and this model is one combination within that range. The right choice depends on how many circuits the cable assembly carries, the current on the power lines and the room the panel gives you. Describe the load and the envelope and we will confirm the shell size and arrangement that fit.
Once the coupling is fully seated the threads stay engaged and the insert holds the contacts in position, which is why this coupling style appears on airframe, vehicle and launcher harnesses. Strain relief at the rear of the shell takes the pull off the contacts instead of letting the wires load them directly. If your installation has a specific vibration profile, share it and we will confirm the shell suits it.
