Sealed Masterplug brand telephone extension cable. To allow an additional phone to be installed up to 20m from an existing BT socket. Has one pre-wired male end to plug into an existing phone socket and the other, female, end needs wired once positioned. Instructions to do so are on rear of packaging. This means that the cable can be cut to length for a neater finish. Also includes an adapter so a phone can still be used in the original socket.
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