Specially designed 2 Way RJ11 Splitter lets you plug in 2 phone devices to 1 wall jack. It allows two telephone or modem with plug to connect to a single telephone socket. This Telephone Splitter is very simple to use. You just plug the adaptor into the RJ11 phone socket, and plug your RJ11 cables (not supplied) into the adaptor, and that's it your done! One end is 6P4C male plug and the other end is two 6P4C RJ11 sockets. other end is two 6P4C RJ11 sockets.