Agender changeror "gender-bender", is a hardware device placed between two cableconnectorsof the same type andgender. An example is a cable connector shell with either two female or two male connectors on it (male-to-male or female-to-female), used to correct the mismatches that result when interconnecting two devices or cables with the same gender of connector.
Gender changers are used forRS-232C ports in either the originalDB-25or theIBM ATDE-9format. They are also used when extending any sort of cable that normally has plugs on both ends (rather than a socket on one and plug on the other), however in this case it is usually called just an "extender", such as withF connectors,BNC connectors, and variousRJ connectorsused intelephonyandcomputer networking.
Thenull modemis a computer communications adapter which may appear to be a gender changer, but it reroutes the wiring. The "transmit" pair from each side is routed into the "receive" pair of the other side, in the manner of acrossover cable.