BG Nexus Brushed Steel Single Master Telephone Socket NBSBTM1 with 25mm Steel Back BoxBG Nexus Brushed Steel Single Master Telephone Socket NBSBTM1 with 25mm Steel Back Box This master telephone socket from British General uses a screw terminal connection and should be used where your telephone line enters your property. This is the best place to connect your router as it's where you're most likely to get the best performance and fastest speeds for your broadband. If you have more than one socket, the master socket is the one that will