One Gang Non-Metallic Romex Box - 18.5 Cu. In.

Southwire #: MSB1G Model #: MSB1G

MSB1G 1 GANG DEVICE BOX 18.5 CU IN

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Features & Benefits

  • One-piece, thick wall molded construction for stability and rigidity
  • Wire entrance clamps on top of bottom of box
  • Mounts to wood wood or metal studs 25g.
  • 6-32 threaded device holes
  • 42 lbs. mounting screws provided
  • UL Classified for 2-hour fire wall
  • UL Listed & RoHS Compliant

Specifications

Model # MSB1G MSB1G
UPC # 784297017629 784297017629
Product Height 3.7 9.40 inch cm
Product Width 2.4 6.10 inch cm
Depth 3.8 9.65 inch cm
Product Weight 0.2 0.09 lbs kg
Material PVC PVC
Cubic Capacity 18.5 (303.2) 18.5 (303.2)
Standard Package 24 24
Rated 4 out of 5 by from Video is little help Video is too far away and shows nothing regarding the Romex clamp's use. Assume I remove the center piece? What about 12 vs.14 wire having only 2 access each? What about larger wire sizes?
Date published: 2022-09-06
Rated 1 out of 5 by from Internal Clamps Are Showstoppers Thought I'd try one. Nice box, great mounting alternative but internal cable clamps are a disaster. Can't easily feed wire though clamps as they are far too stiff, have to fight feeding wire through! Clamp opening appears to take only one wire. Clamps need a redesign. Carlton old work box clamps are much better!.
Date published: 2024-03-22
Rated 1 out of 5 by from trash Echoing the other reviews. The clamps are needlessly hard to open. The Southwire documentation is terrible. Getting it parallel with the sheet rock is needlessly difficult. This is just a terrible product all around.
Date published: 2024-06-05
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Are the fasteners exterior rated?  I need to use the box on an exterior patio and wasn’t sure if the screws are rated for exterior use. 

Asked by: Exterior rating
The screws are not intended to be used in the weather. If they are going to be covered behind a wall outdoors, then they should be fine, but we wouldn't recommend placing them in a place where they will be overexposed to the elements.
Answered by: Southwire1
Date published: 2023-03-16

Can you tell me this single gang box have a CE Certifacte ?

Asked by: Piotr
This product is not listed as having CE certification. However, it is UL Listed & RoHS Compliant. If you need additional assistance, please do not hesitate to reach out to us at 855-798-6657.
Answered by: Southwire1
Date published: 2023-02-07

Does the UL rating allow for two 12/2 NM cables to be installed through a single #12 labeled clamp?

Asked by: iepxs
We are happy to help! Please consult with our experts at CableTechSupport@southwire.com for assistance regarding your question.
Answered by: Southwire1
Date published: 2024-09-14

Can you install a #12 wire in the #14 slot on your smartbox products as long as you stay within the fill capacity.

Asked by: Mcanton
These clamps are approved by UL for #14 wire. #12 will fit in them, but may not pass an inspection based on how the UL was approved.
Answered by: Southwire1
Date published: 2023-06-22

The Southwire MSB1G and MSB2G electrical smart-boxes say that they are UL Classified for 2-hour fire wall. Do they need fire putty or anything additional to maintain that rating?

Asked by: Jim Mich
The product itself is UL Classified and does not need anything additional to be rated. For additional assistance regarding the product or installation, please contact our team at 855-798-6657 and we'd be happy to help!
Answered by: Southwire1
Date published: 2022-07-21

What's the proper technique for getting wire into the box? Should I break off the V-shaped tabs? I feel like I'm missing something obvious.

Asked by: Jon K
Hi Jon, To activate the wire entrance clamps on the back of the box, insert a flat screw driver into the V shape to free the clamp panels. Once the clamp tabs are free, insert the chosen wire through the clamp to securely hold them in place within the box. For additional assistance, please contact our team at 855-798-6657 and we'd be happy to help further assist.
Answered by: Southwire1
Date published: 2023-09-06

Where is this manufactured?

Asked by: j9i1rj
This product is made from globally sourced parts.
Answered by: Southwire1
Date published: 2023-09-06
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