Modular connector

It is common to use a registered jack number to refer to the physical connector itself; for instance, the 8P8C modular connector type is often labeled RJ45 because the registered jack standard of that name specified 8P8C modular connectors. Similarly, various six-position modular connectors may be called RJ11. Likewise, the 4P4C connector is sometimes called RJ9 or RJ22 though no such official designations exist. 6P2C used for telephone line connections