Discover a wide choice of RJ11 cables and a whole range of essential accessories for your landline telephone . The Registered jack 11 is an international standard used both by landline telephones and in the field of local networks. RJ11 telephone cable , telephone jack , establish the connection between your ADSL filter and your modem / router without fear of induction of external interference. The RJ11 / RJ45 adapter cables allow you to connect your RJ45 wall socket to your device equipped with an RJ11 socket: telephone, fax or modem. These cables can also be used with multifunction printers /fax machines.