Crouse-Hinds 4" Steel Square E...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$3.65
Eaton Crouse-Hinds 4" Steel Square Extension Rings - 1-1/2" Deep with Conduit Knockouts

Crouse-Hinds 4" Steel Square Extension Ring 1-1/2" Deep with Conduit Knockouts

(No reviews yet) Write a Review

Model: TP428

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

$3.65
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

Crouse-Hinds 4" Steel Square Extension Ring 1-1/2" Deep with Conduit Knockouts

Professional electrical box extension for versatile wiring applications

The Crouse-Hinds 4" Steel Square Extension Ring delivers reliable electrical box extension capabilities with 1-1/2" depth and 21 cubic inch capacity. Constructed from drawn steel with integrated conduit knockouts, this extension ring provides professional-grade performance for ordinary/non-hazardous locations while meeting NEC/CEC standards for electrical installations.

Professional Features & Benefits

  • 4" Square Design: Standard size compatibility ensures seamless integration with existing electrical box systems
  • 1-1/2" Depth: Provides additional wiring space and accommodates increased conductor capacity requirements
  • 21 Cubic Inch Capacity: Generous internal volume supports multiple conductors and connections per code requirements
  • Drawn Steel Construction: Durable material construction delivers long-term structural integrity and corrosion resistance
  • Conduit Knockouts: Pre-formed entry points facilitate efficient conduit connections and professional installations
  • NEC/CEC Compliance: Meets established electrical code standards for safe and compliant installations
  • Lightweight Design: At 0.46 lb, provides easy handling and installation without compromising structural strength

Technical Specifications

  • Area Classification: Ordinary/Non-Hazardous Locations
  • Box Size: 4"
  • Capacity: 21 cubic in
  • Construction: Drawn
  • Depth: 1-1/2"
  • Product Height: 1.5 in
  • Product Length Depth: 4 in
  • Product Material: Steel
  • Product Weight: .46 lb
  • Product Width: 4 in
  • Standards Type: NEC/CEC

Professional Applications

  • Residential electrical installations requiring additional box depth
  • Commercial building electrical systems
  • Industrial facility wiring applications
  • Electrical panel and junction box extensions
  • Code-compliant electrical box modifications
  • Professional electrical contractor projects

Why Choose Crouse-Hinds Quality?

Crouse-Hinds extension rings deliver proven reliability through drawn steel construction and NEC/CEC compliance. The lightweight yet durable design ensures professional installation efficiency while maintaining long-term structural integrity for demanding electrical applications.

Manufacturer Resources

Product Specs

Area Classification:
Ordinary/Non-Hazardous Locations
Box Size:
4"
Capacity:
21 cubic in
Construction:
Drawn
Product Height:
1.5 in
Product Length Depth:
4 in
Product Material:
Steel
Product Weight:
.46 lb
Product Width:
4 in
Standards Type:
NEC/CEC
Product Depth:
1-1/2"
Department:
Electrical
Product Type:
Box Extension Ring
Product Subgroup:
Electrical Boxes
Product Group:
Boxes & Enclosures

Crouse-Hinds TP428 – Frequently Asked Questions

1) What is the difference between the Crouse-Hinds TP424, TP426 and TP428 extension rings?
Only the side knockout pattern. All three are the same 4 inch square, 1-1/2 inch deep steel ring with 21 cubic inch capacity. TP424 has twelve 1/2 inch side knockouts, TP426 has eight 3/4 inch, and TP428 is the mixed one with eight 1/2 inch plus four 3/4 inch. Pick by the trade size of the conduit or connectors landing in the sides: all 1/2 inch EMT, all 3/4 inch, or a run that mixes both.
2) Which extension ring do I order if I am running 3/4 inch EMT into the sides?
The TP426. It carries eight 3/4 inch side knockouts, so every entry takes a 3/4 inch connector without a reducing washer. If part of the job is 1/2 inch and part is 3/4 inch, the TP428 gives you eight 1/2 inch and four 3/4 inch on the same ring. Going all 1/2 inch, the TP424 has twelve of them.
3) I need to bring a recessed 4 inch square box out flush with new drywall. Will this ring do it?
That is the job it is built for. The ring stacks on the existing box and brings the opening forward 1-1/2 inches, which covers a box buried behind a layer of new board, furring or added finish. If the box is set deeper than 1-1/2 inches, you either stack a second ring or use a deeper one. Devices and covers then mount to the ring rather than the original box.
4) Does a Crouse-Hinds TP424 extension ring meet NEC requirements for added box volume?
The ring is built to NEC/CEC standards and its 21 cubic inch capacity is what you add to the box volume in your fill calculation. Steel construction means it also stays in the equipment grounding path through the mounting screws and conduit connections, which a plastic ring on a metal box would not do.
5) Is a drawn steel extension ring stronger than a welded one?
Drawn means the body is formed from a single piece of steel with no welded corner seams, so there is no joint to split when the ring is torqued down or a heavy conduit run pulls on a knockout. For a fleet of openings or a facility standardizing on one part, the drawn steel body is the difference worth knowing between this and a fabricated ring.
How fast can I get the Crouse-Hinds TP428 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 Crouse-Hinds TP428 come with a warranty?
Absolutely. The Crouse-Hinds TP428 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 Crouse-Hinds TP428?
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 Crouse-Hinds TP428 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!