This is the standard 'large' BT master socket. Although BT rules prevent you working on the network side of their master, there is nothing to stop you installing your own NTE5 downstream. This new NTE5 can be then used to fit a faceplate splitter as the basis of a flexible approach to wiring your premises for ADSL. Uses screw terminals for connection to the main incoming telephone line pair. The NTE5 measures 84mm square