Knightsbridge 47mm Double Pattress Box with Earth Terminal - White

The Knightsbridge SN1600 is a 47mm deep double-gang surface-mount pattress box moulded from white thermoset resin, designed to house two-gang switches, sockets or other modular wiring accessories where flush mounting is not possible. An integrated earth terminal and cable strain relief are built into the back of the box, eliminating the need for separate earthing connectors during installation.

Designed for residential, commercial and industrial installation where cable runs are surface-mounted or where wall construction prevents recessing a back box, the 47mm depth provides sufficient cable management space for typical twin-and-earth wiring on 13A sockets and light switches. The box measures 146mm wide by 86mm high, matching the standard double-gang faceplate footprint used across the Knightsbridge Square Edge (SN) range and most other UK modular accessories.

The white thermoset resin construction is non-combustible and maintains its shape under heat better than thermoplastic alternatives. The box carries an IP20 rating, making it suitable for dry indoor locations but not for bathrooms, outdoor use or environments with moisture exposure. Knightsbridge has tested the resin for anti-microbial properties to ISO 22196:2011, and the box carries a 25-year warranty against manufacturing defects.

Product Specification Sheet

What's the difference between a pattress box and a back box?

A pattress box is a surface-mounted enclosure that sits on the wall surface, whereas a back box is recessed into the wall behind the plaster. Pattress boxes are used where flush mounting is not possible due to solid walls, surface trunking or cable management requirements.

Is the earth terminal required?

Yes, when installing metal faceplates or any accessory that requires an earth connection. The integrated terminal allows you to connect the circuit protective conductor (earth wire) directly to the box, which then earths the faceplate through the fixing screws.

What accessories fit this box?

Any standard UK double-gang modular accessory with an 86mm vertical spacing between fixing centres will fit, including switches, sockets, dimmers and data outlets. The box is designed specifically for the Knightsbridge Square Edge (SN) range but accepts other brands' double-gang faceplates.

Can this be used outdoors or in bathrooms?

No. The IP20 rating means the box is suitable only for dry indoor locations. For bathrooms, outdoor use or other wet environments, you need a weatherproof enclosure with a higher IP rating such as IP55 or IP65.