Solwise ADSL Filtered BT Faceplate.
Integrates an ADSL microfilter into a standard BT socket. Although
supplied with a surface mount back-box for convenience, the faceplate is
replacement compatible with existing BT extension sockets. Connections
are provided at the rear to enable further ordinary extensions to get a
filtered or unfiltered signal. This device is available in two sizes:
The 65mm version is compatible with a standard BT extension socket. The
85mm version matches the standard electical socket of the type used with
plaster/board mount back-boxes.