Orbit 4SB-MKO-FB 4" Square Wel...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$3.01
Orbit 4SB-MKO-FB 4" Square Welded Steel Box with MKO & FB Bracket

Orbit 4SB-MKO-FB 4" Square Welded Steel Box with MKO & FB Bracket

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Model: 4SB-MKO-FB

In Stock (leaves warehouse same day if ordered before 3pm ET)

$3.01
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Orbit 4SB-MKO-FB 4" Square Welded Steel Box with MKO & FB Bracket, 1-1/2" Deep

The Orbit 4SB-MKO-FB is a 4-Inch x 4-Inch x 1-1/2-Inch welded square (4S) electrical box constructed from 16 Gauge sheet steel, delivering 21 cubic inches of usable interior volume for wiring devices, receptacles, and junction connections. This box is factory-equipped with an MKO bracket and an FB bracket, giving installers a pre-configured mounting solution for fast, secure placement in new construction and remodel electrical rough-in work. The fully welded seam construction provides a rigid, one-piece box body that resists flexing during installation, while the compact 1-1/2" depth keeps the box profile low for standard wall and stud-cavity applications. Backed by the Orbit name, this 4S box is built to standard electrical box dimensions so it integrates cleanly with common covers, mud rings, and device plates sized for the 4-Inch square footprint.

Key Features

  • Box Size: 4-Inch x 4-Inch x 1-1/2-Inch deep square (4S) configuration for standard device and junction installations.
  • Durable Construction: Fabricated from 16 Gauge sheet steel for a rigid, impact-resistant box body.
  • Welded Seams: Fully welded corner and seam construction for a solid, one-piece box that holds its shape during handling and installation.
  • Interior Capacity: 21 cubic inches of usable volume to accommodate devices, splices, and conductors per code fill requirements.
  • Integrated Mounting Brackets: Equipped with both MKO and FB brackets for versatile, ready-to-install mounting without sourcing separate hardware.
  • Standard 4S Footprint: 4-Inch square dimensions are compatible with common 4-Inch square covers, mud rings, and device plates.

Technical Specifications

  • Box Type: 4" Square (4S) Welded Box
  • Dimensions: 4-Inch x 4-Inch x 1-1/2-Inch
  • Material: 16 Gauge Sheet Steel
  • Interior Volume: 21 Cubic Inches
  • Mounting Brackets: MKO and FB Brackets Included

Typical Applications

  • Residential and Commercial Wall Rough-In
  • Receptacle and Switch Device Mounting
  • Junction and Splice Point Installations
  • New Construction Electrical Framing
  • Stud-Mounted Electrical Box Applications

Why Orbit?

Orbit engineers this 4S square box from durable 16 Gauge welded steel, giving electricians a rigid, dependable enclosure that stands up to jobsite handling. With the MKO and FB brackets already integrated, this box streamlines installation for professionals who need a reliable, code-ready electrical box without assembling separate mounting hardware.

Manufacturer Resources

Product Specs

list_batch:
ORB-20260924
Product Type:
Outlet Box
Configuration:
MKO & FB Bracket
Product Finish:
16 Gauge Sheet Steel
Department:
Electrical
Product Subgroup:
Electrical Boxes
Product Material:
Steel
Product Size:
1-1/2"
Product Group:
Boxes & Enclosures

Orbit 4SB-MKO-FB – Frequently Asked Questions

1) How many conductors can I put in an Orbit 4SB-MKO-FB 4 inch square box?
The 4SB-MKO-FB holds 21 cubic inches, which is what you work your box fill from. At 2.25 cu in per 14 AWG conductor that's 9 conductors, or 8 at 2.00 cu in for 12 AWG, before deductions for devices, clamps and grounds. Add back volume if you install a raised mud ring.
2) Will standard 4 inch square covers and mud rings fit the Orbit 4SB-MKO-FB?
Yes. It's a standard 4S footprint, 4 x 4 inches, so common 4 inch square flat covers, raised device rings and plates sized for 4S all land on it. The brackets don't change the cover pattern.
3) Is a 1-1/2 inch deep box deep enough, or should I use a 2-1/8 inch 4S box?
The 4SB-MKO-FB is the shallow 1-1/2 inch depth at 21 cubic inches. It's fine for a device or two and a few splices in a standard stud cavity. If you're pulling multiple circuits through, feeding a junction point, or stacking a device plus clamps and grounds, step up to the deeper 2-1/8 inch 4S box (about 30.3 cu in) instead of fighting the fill calculation.
4) What are the MKO and FB brackets on this Orbit square box for?
Both brackets come welded on from the factory, so the box ships ready to mount to framing without you buying separate hardware. That's the point of the -MKO-FB suffix: it's the same 4S box body with the mounting already integrated for stud and framing rough-in.
5) What gauge steel is the Orbit 4SB-MKO-FB made from, and is it welded or crimped?
16 gauge sheet steel with fully welded corners and seams, so the body is one rigid piece. Welded construction matters on a jobsite box because it won't rack or spring out of square when you're hammering brackets to a stud or pulling wire through it.
6) Can I use this Orbit 4S box for a receptacle or switch, or is it junction only?
Both. It's rated by volume for device mounting as well as splices, so you can land a receptacle or switch in it with a mud ring, or use it as a pure junction and splice point. Typical uses run from residential and commercial wall rough-in to new construction framing.
7) Does this box work for a remodel or old-work installation?
It's built for rough-in where you can reach the framing. The MKO and FB brackets fasten to a stud, so the wall has to be open or the framing accessible. For cutting into finished drywall with no stud access, you want an old-work box with wing clamps, not a bracketed 4S.
8) What is the Orbit part number for the 4 inch square box with MKO and FB brackets?
Orbit MPN 4SB-MKO-FB. The 4SB is the 4 inch square box body, and the MKO-FB suffix identifies the bracket configuration. Only one size is built in this configuration, the 1-1/2 inch depth.
How fast can I get the Orbit 4SB-MKO-FB delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Orbit 4SB-MKO-FB come with a warranty?
Absolutely. The Orbit 4SB-MKO-FB is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Orbit 4SB-MKO-FB?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Orbit 4SB-MKO-FB from ZenSupply?
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