Wall Mount Receptacle, 56 Contacts (48× #20 + 8× #8) Socket, Shell 25, Olive Drab — MIL-DTL-38999 III

Specifications

Cross-Brand Compatibility

Applications

The D38999/20JJ4JN is the socket version of the shell 25 J-4 wall mounting receptacle: 56 contacts in total, made up of 48 signal positions at contact size #20 and 8 power positions at size #8. Wall mount receptacles bolt through a square flange to a bulkhead or equipment rack; the socket contacts are the fixed half that the plug’s pins enter. Series III’s triple-start thread and self-locking ratchet make it scoop-proof and resistant to vibration loosening, which is why the arrangement is used across helicopter, fixed-wing and ground-vehicle harnesses.

DLA Land and Maritime solicited this part number on DIBBS solicitation SPE7M526T507X (NSN 5935-01-555-8529), quantity 108 EA, quotations due 27 September 2026. The procurement supports the MH-60R helicopter platform and requires a qualified-products-list source.