TBJJA75 Bulkhead Jack to Jack 75 Ohm Adaptor

TNC Bulkhead Jack - Jack 75 Ohm Singel Hole Fixing Adaptor.

The TNC connector is a threaded version of the BNC connector. The TNC connector in usually 50 Ω impedance and operates best in the 0–11 GHz frequency spectrum. It has better performance than the BNC connector at microwave frequencies.
It was commonly used by the military for radiom communication and radar applications and has been used in a wide range of radio and wired applications.
The TNC CDonnector was designed in the late 1950s and named after Paul Neill of Bell Labs and Carl Concelman of Amphenol,

Reverse-polarity TNC is a variation of the original TNC specification which reverses the polarity of the mating face.
This is usually achieved by swaping the female contacts normally found in jacks into the plug, and the male contacts normally found in plugs into the jack.

Most TNC connectors are 50-ohm type even when used with coaxial cable of other impedances, but a 75-ohm TNC connector is also available.
These can be recognized by a reduced amount of dielectric in the mating ends. They are intermatable with standard 50 ohm connectors.

TNC Bulkhead Female - Female 75 Ohm Singel Hole Fixing Adaptor. -Greenpar Equivalent T37R53J999X99