BT Master Telephone Outlet Module 25 x 50mm IDC - Black

The Knightsbridge BT master telephone outlet module is a 25 x 50mm single-width euro-module designed for installation in modular grid faceplates. The module provides a master BT socket with IDC (insulation displacement connector) terminals on the rear, allowing telephone cable to be terminated without stripping the insulation from individual conductors.

Designed for residential and light commercial telephone wiring, the module fits standard 25mm minimum depth back boxes and clips into any compatible euro-module faceplate alongside other modules (data, TV, audio, switches). The master socket designation means it is the first socket in a telephone extension chain, providing the main connection point from the incoming telephone line before additional extension sockets are wired downstream.

The black ABS construction carries an IP20 rating for standard dry indoor use and is certified to BS 5733, the British Standard covering telephone plugs and socket outlets. The 21mm recessed depth allows the module to sit flush within a faceplate without protruding beyond the wall surface once installed.

Product Specification Sheet

What is a master socket?

A master socket is the first telephone socket in a wiring chain, taking the incoming line directly from the service provider. Extension sockets are then wired from the master. If you experience line faults, testing at the master socket helps isolate whether the issue is in your internal wiring or on the external line.

What are IDC terminals?

IDC stands for insulation displacement connector. The terminals have sharp blades that cut through the cable insulation when the conductor is pushed in, making contact with the copper core without needing to strip the wire first. This speeds up installation and reduces the chance of mis-wiring.

What faceplate does this fit?

This module fits any euro-module grid faceplate with 25mm-wide apertures. Knightsbridge produces compatible faceplates in various finishes and gang configurations. The module is 25mm wide (single-width), so a 2-gang euro-module plate could accommodate two of these modules side by side, or one telephone module alongside a data or TV module.

Can this be used for broadband?

The module provides a standard BT telephone socket which can carry both voice and ADSL broadband signals. For VDSL or fibre broadband you would typically use a filtered faceplate or a separate broadband-specific module to avoid interference between voice and data signals on the same line.