Wiremold B-3 Deep 1-Gang Metal Raceway Outlet Box 1.37"

Wiremold B-3 is a 1-gang, 1.37-inch-deep metal surface-mount outlet box designed to give extra depth for dimmers, GFCIs and oversized devices while matching walls in an ivory finish.

This compact surface-raceway component from Wiremold’s 500 Series provides a simple, clean way to extend power and install larger electrical devices without cutting into walls. Made of durable metal and finished in paintable ivory, the B-3 deep outlet box adapts an existing outlet into the start point for surface wiring runs, supports heavier devices like speed controls and GFCIs, and meets UP approval for surface wiring systems.

How does this box help when I need to install a dimmer or a GFCI?

The extra depth (1 3/8" / 1.37") gives room for bulkier devices that won’t fit in a standard shallow box, preventing pinched wires and crowded terminals. It mounts in a surface-raceway setup so you can add the device where you need it without opening the wall.

• Provides 1.37" internal depth for dimmers, speed controls, and GFCIs
• 1-gang size accommodates most residential wiring devices
• Metal construction reduces damage risk and supports heavier devices
• Paintable ivory finish blends with decor

Will this fit into a Wiremold surface raceway system and how is it installed?

The B-3 is built for Wiremold surface wiring installations — it connects to raceway runs to create a continuous wiring path. Installation is straightforward for a handyman or electrician: secure the box at the chosen location, route the raceway and cables, then mount the device and cover plate.

• Designed to integrate with Wiremold 500 Series raceways
• Screw mounting points for secure attachment to wall surfaces
• Allows simple wiring access for adding outlets or switches
• Paintable surface to match surrounding walls after install

What materials and finish does the B-3 use, and is it durable?

Constructed of metal, the deep outlet box resists wear and supports heavier electrical devices better than thin plastic alternatives. The ivory finish is factory-applied and can be painted to coordinate with any room palette, making it both a practical and visually adaptable component.

• Robust metal housing for mechanical strength
• Ivory factory finish; paintable for custom color matching
• Manufactured to Wiremold quality standards for longevity
• Suitable for residential and light commercial applications

Can I use this for new wiring runs on brick or concrete walls?

Yes — surface wiring with Wiremold products is ideal for masonry where in-wall wiring is difficult or costly. The B-3 lets you add an outlet or switch on surface-mounted raceway and continue runs across brick or concrete with minimal modification.

• Works well on brick, concrete, or finished surfaces where cutting is undesirable
• Creates an accessible starting point for surface wiring runs
• Reduces installation time compared with opening walls for new wiring
• UP-approved for surface raceway systems where applicable

Who is this product for? The Wiremold B-3 deep metal outlet box is aimed at electricians, contractors, and DIYers who need a dependable surface-mount solution for larger devices — dimmers, GFCIs, and speed controls — or for anyone extending power on finished or masonry surfaces without invasive wall work. It’s also a good choice for commercial and institutional settings that depend on robust, paintable hardware that integrates seamlessly with Wiremold raceways.