"BT I-Plate - Will it work for you?
1. Do you have extension wiring?
Extension wiring is the telephone wiring, usually a small white cable, which often runs along your skirting boards or outside your house. It connects the main socket to any extension sockets you have. It doesn't matter if you use the sockets or not, as long as the wiring is there the I-Plate may help."
Not sure if that answers your question or not!