4 HOLE 1/2 INCH BOX EXTENSION
Manufacturer Resources
Product Specs
- Cable Entry Position:
- Threaded Hubs
- Product Group:
- Electrical Boxes
- Product Type:
- Electrical box extension
- Product type2:
- Electrical box extension
- Selling Unit Of Measure:
- each
- Standards:
- CSA 703005
- Department:
- Electrical
- Product Subgroup:
- Outlet Boxes
- Product Material:
- Aluminum Alloy
Red Dot S121E-R – Frequently Asked Questions
1) What does the Red Dot S121E-R box extension do, and when would an electrician use one?
The S121E-R is a box extension that mounts on an existing outlet box to add depth and give you four 1/2 inch threaded hubs for conduit entry. It is the part you reach for when the existing box runs out of room for conductors or device wiring, or when you need additional threaded conduit entries off that box. Sold individually.
2) Do the openings on the S121E-R take 1/2 inch conduit directly, or do I need connectors?
The four openings are threaded 1/2 inch hubs, so 1/2 inch rigid or IMC conduit and 1/2 inch threaded fittings thread straight in. They are not knockouts, so no separate box connector is needed for threaded conduit. For 1/2 inch EMT you would still use a threaded EMT connector into the hub.
3) Is the Red Dot S121E-R metal or plastic, and will it hold up outdoors?
It is cast aluminum alloy, not plastic, so it is corrosion resistant and suits the same exterior and damp-location work the rest of the Red Dot cast line is used for. Aluminum also means it bonds as part of the metallic raceway system when threaded conduit is installed in the hubs.
4) What part number do I order for the Red Dot four-hole 1/2 inch box extension?
Order Red Dot S121E-R. That is the manufacturer part number for the four-hole, 1/2 inch hub aluminum box extension, and it ships as a single piece rather than a carton quantity.
5) Can I use the S121E-R to add conduit runs to a box that is already full of wires?
That is the usual reason to install one. Stacking the extension on the existing box adds interior volume for conductors and gives four more 1/2 inch threaded entries for additional conduit runs, so you can branch off an existing box without replacing it. Fill calculations still have to be worked for the combined assembly.
6) Is the Red Dot S121E-R made in the USA?
Country of origin is listed as India or Mexico. That matters on jobs with domestic-sourcing requirements, so it is worth confirming against the spec on government or federally funded work.
How fast can I get the Red Dot S121E-R 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 Red Dot S121E-R come with a warranty?
Absolutely. The Red Dot S121E-R 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 Red Dot S121E-R?
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
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