Gender changer

Gender changers are used for RS-232C ports in either the original DB-25 or the IBM AT DE-9 format.

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 with F connectors, BNC connectors, and various RJ connectors used in telephony and computer networking.

The null modem is a computer communications adapter which may appear to be a gender changer, but it reroutes the wiring.

Many different types of small hardware can be considered gender changers.

For instance, there are a variety of small adapters sold for quarter-inch audiovisual cables that serve the role of connecting gendered cables.