Aviation Connector Circular Electrical Rfi Connector J599/26fj38sb
J599/26FJ38SB Straight Plug, GJB599 Series III / MIL-DTL-38999 Series III
The J599/26FJ38SB is a triple-start threaded circular electrical connector plug designed for aerospace, avionics, and industrial platforms. It conforms to GJB599 Series III requirements and is interchangeable with the D38999/26FJ38SB designation used in MIL-DTL-38999 Series III supply chains.
This straight plug features Class F electroless nickel finish, shell size J (shell size 25), insert arrangement J38 / 25-38 (38 contacts: 38 x #22D signal), socket contacts (S), and keying position B (not normal N). The design supports EMI shielding, scoop-proof mating, self-locking threaded coupling, and removable crimp contacts.
Product Features
- Conformant to GJB599 Series III (equivalent to MIL-DTL-38999 Series III / D38999)
- Interchangeable with cross-reference part number D38999/26FJ38SB
- Triple-start threaded self-locking coupling for high-vibration retention
- Straight plug style for cable-end termination
- Class F electroless nickel shell finish for corrosion resistance and conductivity
- Sealed signal-only configuration (S) with insert arrangement J38 / 25-38: 38 x #22D signal contacts (Service Class M - sealed)
- Keying position B for polarization and anti-mismatch mating
Technical Specifications - J599/26FJ38SB
| Parameter | Value |
|---|---|
| Part Number | J599/26FJ38SB |
| Equivalent Part Number | D38999/26FJ38SB |
| Series | GJB599 Series III / MIL-DTL-38999 Series III |
| Connector Type | Straight plug (J599/26 / D38999/26) |
| Coupling | Triple-start threaded, self-locking |
| Finish Class | F - Electroless nickel plating |
| Shell Size | J (numeric shell size 25) |
| Insert Arrangement | J38 / 25-38 (38 contacts: 38 x #22D signal) |
| Contact Gender | S - Socket contacts (crimp, removable) |
| Keying / Polarization | B - Keying position B (not normal; will not mate with keying N) |
| Cable End Style | Straight plug (backshell / accessory attach as required) |
| Shielding | EMI shielded (conductive shell finish) |
| Operating Temperature | Approximately -65°C to +200°C (Class F) |
| Suffix Designation | None — keying B is the trailing segment (not a suffix) |
| Compatible Mating | J599/20FJ38PB or J599/24FJ38PB receptacle (or D38999 equivalents), shell size J, arrangement 38, pin contacts, keying B |
Part Number Breakdown
| Segment | Meaning |
|---|---|
| J599 | GJB599 Series III circular connector family (D38999 equivalent) |
| /26 | Straight plug |
| F | Electroless nickel finish (Class F) |
| J | Shell size J (shell size 25) |
| 38 | Insert arrangement 38 (J38 / 25-38, 38 x #22D signal) |
| S | Socket contacts |
| B | Keying position B |
Related options: J599/26WJ38SB uses olive drab cadmium finish (W); J599/26KJ38SB uses stainless Class K; pin contact version is J599/26FJ38PB; mating square-flange receptacle is J599/20FJ38PB; jam-nut receptacle is J599/24FJ38PB. Same shell size also commonly uses arrangements J19 (19 x #22D sealed signal) and J53 (53 x #22D high-density signal). Keying B is incompatible with keying N receptacles — ensure all mating parts use the same keying position. There is no functional difference between J599 and D38999 prefixes for form-fit-function mating within the same Series III family.
Compatible Applications
The J599/26FJ38SB straight plug is intended for platforms that require EMI-capable threaded interconnects with mid-density signal circuits in shell size J (25), using keying position B. Typical use cases include:
- Aircraft and helicopter wiring harness cable ends
- Avionics LRUs, radar, and communication equipment
- Ground vehicles and rugged electronic enclosures
- Shipboard and outdoor equipment requiring sealed circular connectors
- Industrial systems that standardize on GJB599 / MIL-DTL-38999 Series III interfaces
Selection Guide
| Requirement | Recommended Choice |
|---|---|
| Straight plug, size J / arrangement 38 / sockets / keying B / nickel | J599/26FJ38SB - this product |
| Same plug with olive drab cadmium finish | J599/26WJ38SB |
| Same plug with stainless Class K finish | J599/26KJ38SB |
| Matching square flange receptacle with pin contacts | J599/20FJ38PB / D38999/20FJ38PB |
| Matching jam-nut receptacle with pin contacts | J599/24FJ38PB / D38999/24FJ38PB |
| Pin contact version of this plug | J599/26FJ38PB |
| Higher-density signal layout in shell size J | J599/26FJ53SB |
Installation Notes
- Verify shell size, insert arrangement, contact gender, finish class, and keying position B before mating.
- Use the correct crimp tooling for #22D signal contacts specified by arrangement J38 / 25-38.
- Select and install a compatible M85049 / GJB1784 backshell or strain relief for shell size 25.
- Fully engage the triple-start threaded coupling until the self-locking mechanism is seated.
- Mate only with Series III receptacles of the same shell size, arrangement, opposite contact gender, and keying position B (keying N is not compatible).
Why Choose J599/26FJ38SB
Form-Fit-Function Compatibility
Choosing J599/26FJ38SB ensures form-fit-function compatibility with D38999/26FJ38SB supply chains while meeting GJB599 Series III requirements. The straight plug geometry supports secure mating, EMI continuity, and reliable mid-density signal interconnect with keying B polarization in aerospace and industrial systems.
Ordering Information
Order by the GJB599 designation J599/26FJ38SB, or cross-reference as D38999/26FJ38SB, depending on your procurement standard. When requesting a quote, please confirm mating receptacle part number (must use keying B), backshell / accessory needs, contact plating, and required quantity.
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