This telephone extension cable is specifically designed to connect BT master sockets to routers or telephones. It is a standard 56K cable for telephone line connections (such as modems) but does not support broadband (ADSL requires an RJ11-to-RJ11 cable). Easy plug-and-play setup—no extra tools or technical skills required. Simply plug one end into the BT master socket and the other into your telephone or modem/router. This cable features high-quality shielded materials for stable, high-speed performance, suitable for all types of users. This durable flat BT-to-RJ11 telephone cable features advanced shielding for superior longevity. It is compatible with various devices, including modems, telephones, fax machines, Sky boxes, and more, connecting seamlessly to BT sockets. Before purchasing this 2-wire telephone cable, ensure your device supports a two-pin cross-connect cable (Tip: If your current cable has two connectors at the BT socket end, this cable is likely compatible). We strive for excellence—this cable has been fully redesigned to deliver unmatched durability, stability, and precise compatibility.