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3 Gang 35mm Single + Double Galvanised Steel Back Box

£199
The RRP is the manufacturer's recommended retail price of the item.
Limited Stock
We are an Independent UK Company
Price match. Found it cheaper? Contact us
Trade Discount Available

Minimum order for this item is 5.

Description

The Knightsbridge 3-gang 35mm galvanised steel back box mounts two wiring accessory plates side-by-side in a single cut-out: one 1-gang plate (86 x 86mm) and one 2-gang plate (86 x 146mm). The box measures 220mm wide, 73mm high and recesses 35mm into the wall, providing sufficient internal space for standard cable runs and terminal connections behind both plates.

Designed for new-build and retrofit electrical installation in residential, commercial and light industrial settings, the box is manufactured from 1mm-thick galvanised steel to EN 60670, offering corrosion resistance and structural rigidity for plasterboard and masonry mounting. Four fixed mounting lugs provide secure fixing points, and the 20mm knockouts on all four sides accept standard conduit and cable entry.

The integrated earth terminals allow safe bonding of metal faceplates and accessories. The galvanised finish prevents rust in damp environments during first-fix installation before the wall is plastered and decorated. This box is compatible with standard 86 x 86mm and 86 x 146mm UK wiring accessory plates only — not oversized or non-standard plates.

Specification
Height 73 mm
Width 220 mm
Recessed Depth 35 mm
Construction Steel
Earth Terminal Yes
Warranty 25
Downloads

Product Specification Sheet

Frequently Asked

What plate sizes does this box accept?

This box accepts one 1-gang plate (86 x 86mm) and one 2-gang plate (86 x 146mm) mounted side-by-side. It is not compatible with oversized or non-standard UK plate dimensions.

What wall thickness is needed?

The box recesses 35mm into the wall. For plasterboard installation, a minimum 35mm cavity depth is required behind the board. For masonry, a 35mm-deep chase must be cut to sit the box flush with the finished wall surface.

Are earth terminals included?

Yes. The box includes integrated earth terminals for bonding metal faceplates and ensuring safe earthing of the accessories mounted in the box.

What are the knockouts for?

The 20mm knockouts on all four sides accept standard conduit and cable entry. Remove the knockout appropriate to your cable run direction during first-fix installation.

Shipping & Returns

Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

To arrange a return, call us on 020 8149 5199 or use our contact page.

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Why Niori

Over 20 years lighting homes worldwide

We are a specialist lighting and mirror retailer with showrooms in Birmingham, Hong Kong and Dubai, shipping to customers around the world. Our own design team is here to help, from first idea to final fitting.

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Every product arrives brand new with the full manufacturer warranty. Found it cheaper elsewhere? Ask us about a price match.

Installation

Fits standard UK back boxes

Designed to fit standard UK back boxes for a straightforward swap of your existing fittings.

Ordering with us

Free delivery over £99

Free delivery on orders over £99, in the UK and worldwide. Easy returns within 14 days, subject to our returns policy. Full manufacturer warranty included.

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    Description

    The Knightsbridge 3-gang 35mm galvanised steel back box mounts two wiring accessory plates side-by-side in a single cut-out: one 1-gang plate (86 x 86mm) and one 2-gang plate (86 x 146mm). The box measures 220mm wide, 73mm high and recesses 35mm into the wall, providing sufficient internal space for standard cable runs and terminal connections behind both plates.

    Designed for new-build and retrofit electrical installation in residential, commercial and light industrial settings, the box is manufactured from 1mm-thick galvanised steel to EN 60670, offering corrosion resistance and structural rigidity for plasterboard and masonry mounting. Four fixed mounting lugs provide secure fixing points, and the 20mm knockouts on all four sides accept standard conduit and cable entry.

    The integrated earth terminals allow safe bonding of metal faceplates and accessories. The galvanised finish prevents rust in damp environments during first-fix installation before the wall is plastered and decorated. This box is compatible with standard 86 x 86mm and 86 x 146mm UK wiring accessory plates only — not oversized or non-standard plates.

    Specification
    Height 73 mm
    Width 220 mm
    Recessed Depth 35 mm
    Construction Steel
    Earth Terminal Yes
    Warranty 25
    Downloads

    Product Specification Sheet

    Frequently Asked

    What plate sizes does this box accept?

    This box accepts one 1-gang plate (86 x 86mm) and one 2-gang plate (86 x 146mm) mounted side-by-side. It is not compatible with oversized or non-standard UK plate dimensions.

    What wall thickness is needed?

    The box recesses 35mm into the wall. For plasterboard installation, a minimum 35mm cavity depth is required behind the board. For masonry, a 35mm-deep chase must be cut to sit the box flush with the finished wall surface.

    Are earth terminals included?

    Yes. The box includes integrated earth terminals for bonding metal faceplates and ensuring safe earthing of the accessories mounted in the box.

    What are the knockouts for?

    The 20mm knockouts on all four sides accept standard conduit and cable entry. Remove the knockout appropriate to your cable run direction during first-fix installation.

    Shipping & Returns

    Delivery UK delivery is £14.99, and delivery is free on all orders of £99 or more, in the UK and internationally.

    Returns If you change your mind, you have 14 days from delivery to tell us, and a further 14 days to send the goods back. Return postage for a change-of-mind return is paid by you. Change-of-mind returns are subject to an inspection and handling deduction. See our full returns policy.

    To arrange a return, call us on 020 8149 5199 or use our contact page.