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Square D QO 40 amps Plug In Single Pole Circuit Breaker
Square D QO 40 amps Plug In Single Pole Circuit Breaker
Square D QO 40 amps Plug In Single Pole Circuit Breaker

Square D QO 40 amps Plug In Single Pole Circuit Breaker

The Square D QO 40 amps Plug-In Single Pole Circuit Breaker is engineered for dependable, straightforward protection inside indoor electrical panels. As part of the trusted QO fami…

Square D MPN QO140CP In Stock & Ready to Ship
Local Price Check i Local stores may price this as low as $16.99. Our online price is $18.99.
$18.99
Includes free shipping on orders over $75 · $8.99 standard below
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You might find it for less locally. Independent retailers often offer competitive pricing — some products are even cheaper in-store than online.
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About Product Overview

The Square D QO 40 amps Plug-In Single Pole Circuit Breaker is engineered for dependable, straightforward protection inside indoor electrical panels. As part of the trusted QO family, this breaker delivers precise overcurrent protection for a single branch circuit, with the reliability you expect from Square D.

  • Amperage and configuration: 40 A, single-pole
  • Voltage rating: 120/240 V
  • Mounting type: Plug-In for quick, secure connection to compatible QO panels
  • Series and branding: QO series from Square D
  • Physical footprint: Width 0.75 in, Depth 3.0 in, Height 0.75 in
  • Indoor use: Designed for indoor panel installations
  • Packaging: Sleeve packaging for safe handling and storage
  • Certifications: UL Listed and CSA Listed
  • Compatibility: Specifically designed for plug-in installation in Square D QO panels

This 40 A plug-in breaker protects high-load branch circuits from overloads, helping keep wiring, devices, and occupants safe. The single-pole design is ideal for dedicated 240 V lines that require robust protection without complicating wiring or panel space. Whether you’re upgrading an aging panel, replacing a failed breaker, or configuring a new circuit, this QO plug-in breaker delivers the reliability you need in everyday residential and light commercial applications.

Practical use cases include safeguarding circuits for large-appliance outlets, heat-pump or air-conditioning circuits, or other 240 V loads where a single-pole 40 A protection device is appropriate. Its plug-in format simplifies installation and replacement in compatible QO panels, reducing downtime and compatibility concerns during electrical work.

Tips for optimal results:

  • Verify your panel is a compatible Square D QO model designed for plug-in breakers before installing.
  • Turn off the main power and confirm the circuit you’re protecting matches the breaker’s 40 A rating.
  • Handle with care to avoid damaging the sleeve packaging and ensure a clean, secure seating in the panel bus.
  • Always follow local electrical codes and, if in doubt, consult a licensed electrician.

The Details Specifications

Brand Square D
SKU 3062361
UPC 047569838019
Unit 0
Case Pack Quantity 10 per case
Retail Unit Quantity 1
Unit of Measure 0 0
Dimensions (L × W × H) 3 × 1 × 3
Weight 0 lbs
Cubic Feet 0.00549 ft³
Country of Origin MEXICO
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab

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The stores we send you to are local and independently run — often for generations, the kind of place where someone behind the counter knows the regulars. We don't own them. We just think they deserve the foot traffic. They can put most of what we sell on their next truck. Ask there before you check out here.

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About our directory. National Hardware Group is an independent retailer and directory. The local stores we list and link to are separately owned and operated — we have no ownership stake in any of them, and most pay us nothing to be included. That includes plenty of stores flying a co-op banner that people don't realize are locally owned and run, not operated by a corporation. Store owners can choose to upgrade their listing for an enhanced presence or pickup features, but the base directory is free, and inclusion is never a paid endorsement.

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