{"product_id":"3-gang-35mm-single-double-galvanised-steel-back-box","title":"3 Gang 35mm Single + Double Galvanised Steel Back Box","description":"\u003ch5\u003eDescription\u003c\/h5\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e\n\u003cp\u003eDesigned 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.\u003c\/p\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e\n\u003ch5\u003eSpecification\u003c\/h5\u003e\n\u003ctable class=\"spec_table\"\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeight\u003c\/td\u003e\n\u003ctd\u003e73 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWidth\u003c\/td\u003e\n\u003ctd\u003e220 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eRecessed Depth\u003c\/td\u003e\n\u003ctd\u003e35 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eConstruction\u003c\/td\u003e\n\u003ctd\u003eSteel\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEarth Terminal\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWarranty\u003c\/td\u003e\n\u003ctd\u003e25\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch5\u003eDownloads\u003c\/h5\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0729\/8993\/3835\/files\/products_2795702_datasheet.pdf\" target=\"_blank\"\u003eProduct Specification Sheet\u003c\/a\u003e\u003c\/p\u003e\n\u003ch5\u003eFrequently Asked\u003c\/h5\u003e\n\u003cp\u003e\u003cstrong\u003eWhat plate sizes does this box accept?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThis 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.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat wall thickness is needed?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eAre earth terminals included?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes. The box includes integrated earth terminals for bonding metal faceplates and ensuring safe earthing of the accessories mounted in the box.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat are the knockouts for?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e","brand":"Knightsbridge","offers":[{"title":"Default Title","offer_id":45293883654411,"sku":"GSK335D","price":1.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0729\/8993\/3835\/files\/177348_0ab07e02-b3f2-4aff-8eb3-56a140e886fc.jpg?v=1714665496","url":"https:\/\/niori.co.uk\/products\/3-gang-35mm-single-double-galvanised-steel-back-box","provider":"Niori","version":"1.0","type":"link"}