Modular Connector - 4P4C

The 4P4C connector, is popularly, but incorrectly, called RJ22, RJ10, or RJ9. It is also commonly referred to as a "Handset Connector" because of the most popular usage for the connector. It is the de facto industry standard for wired telephone handsets. It is used to provide connection from the base of the telephone to the handset.

This handset connector is actually not a registered jack at all, since it was never intended to connect directly to the telephone service lines: RJ connects a phone to the service lines, while 4P4C connects two parts of a phone. Other RJ connector wiring standards are used by telephone companies. The 4P4C is only used for an end user application from the phone to the handset.

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