This is basically a device you plug into your telephone socket (one side). On the other side of it are two holes; one for your ADSL RJ11 cable and one for your telephone line.

Designed by Safecom Technologies Limited for the UK market, it works on all BT Sockets and is ADSL Compliant with SIN346 v2.2 http://safecom.cn/code/sub/category.asp?prdid=209&subcatid=28

Ideal for self-install ADSL broadband and it works with telephones, fax machines, Digiboxes etc. 12 month warranty.

A similar product in Argos is £9.99 !!!