Jam Nut Receptacle, 7× #20 Pin, Shell 11, Aluminium Nickel-PTFE — MIL-DTL-38999 III

Specifications

Cross-Brand Compatibility

Applications

The D38999/24TB99PN is the jam nut receptacle of the shell 11 (B) B99 arrangement — 7× #20 Pin contacts. The final N is the insert polarisation (key) position, which stops a plug being mated to the wrong receptacle of the same arrangement when several connectors share a panel.

Class T uses an aluminium shell finished with nickel-PTFE (a PTFE-loaded nickel plating of the Durmalon family) instead of the cadmium of class W. The PTFE content gives a low-friction, non-galling coupling thread and a hard, electrically conductive surface rated for 500 hours of salt spray, which is why class T is the usual choice where cadmium is prohibited (RoHS / REACH-driven programmes, EU aerospace and much of the commercial avionics market) but the cadmium salt-spray endurance is still wanted. The shell remains aluminium, so weight is unchanged versus class W, and the insert and contact system is identical — the part is form/fit/function interchangeable with every other D38999 Series III connector of the same shell size, insert arrangement, contact gender and key position.