Durable 66 Pin Electrical Connector D38999/26fj5pn by Amphenol

D38999/26FJ5PN Straight Plug, MIL-DTL-38999 Series III / GJB599 Series III

The D38999/26FJ5PN is a triple-start threaded circular electrical connector plug designed for aerospace, avionics, and industrial platforms. It conforms to MIL-DTL-38999 Series III / D38999 requirements and is interchangeable with the J599/26FJ5PN designation used in GJB599 Series III supply chains.

This straight plug features Class F electroless nickel finish, shell size J (shell size 25), insert arrangement J5 / 25-5 (4 contacts), pin contacts (P), and normal keying (N). The design supports EMI shielding, scoop-proof mating, self-locking threaded coupling, and removable crimp contacts.

Product Features

• Conformant to MIL-DTL-38999 Series III / D38999 (equivalent to GJB599 Series III / J599)
• Interchangeable with cross-reference part number J599/26FJ5PN
• 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
• Pin contact configuration (P) with insert arrangement J5 / 25-5: typically 4 x #16 contacts
• Normal keying (N) for standard polarization and anti-mismatch mating

Technical Specifications - D38999/26FJ5PN

Part Number Breakdown

Related options: D38999/26WJ5PN uses olive drab cadmium finish (W); D38999/26KJ5PN uses stainless Class K; socket versions use S contacts; mating square-flange receptacle is D38999/20FJ5SN; jam-nut receptacle is D38999/24FJ5SN. Same shell size also commonly uses arrangements J4, J19, J20, J24, J29, J35, J37, J43, J46, and J61. Confirm contact layout from the Series III arrangement chart when specifying tooling. There is no functional difference between D38999 and J599 prefixes for form-fit-function mating within the same Series III family.

Compatible Applications

The D38999/26FJ5PN straight plug is intended for platforms that require EMI-capable threaded interconnects with a low-count #16 power / signal layout in a large shell. 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 D38999 / GJB599 Series III interfaces

Selection Guide

Installation Notes

• Verify shell size, insert arrangement, contact gender, finish class, and keying before mating.
• Use the correct crimp tooling for #16 contacts specified by arrangement J5 / 25-5; confirm layout from the arrangement chart.
• 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 matching keying.

Why Choose D38999/26FJ5PN

Form-Fit-Function Compatibility

Choosing D38999/26FJ5PN ensures form-fit-function compatibility with J599/26FJ5PN supply chains while meeting MIL-DTL-38999 Series III requirements. The straight plug geometry supports secure mating, EMI continuity, and reliable #16 interconnect in aerospace and industrial systems.

Ordering Information

Order by the D38999 designation D38999/26FJ5PN, or cross-reference as J599/26FJ5PN, depending on your procurement standard. When requesting a quote, please confirm mating receptacle part number, backshell / accessory needs, contact plating, and required quantity.