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Square D QO QOB340 40A 3P 120/240V Bolt-On Circuit Breaker

In stock - 22 items available
SKU: QOB340 UPC: 785901417149
SELECT ITEM CONDITION
Regular price $58.00 USD
Regular price Sale $92.00 USD Sale price $58.00 USD
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Square D QOB340: 40 Amp 3-Pole standard thermal-magnetic circuit breaker, 120/240V, 10kA, bolt-on mount, UL listed.

  • Manufacturer: Schneider Electric
  • Brand: Square D
  • Product Range: QO (for Square D QO loadcenters, NQ and NQOD panelboards and equipment)
  • UPC: 785901417149
  • Model Number: QOB340
  • Breaker Type: Standard
  • Amperage: 40 Amps
  • Poles: 3-Pole
  • Voltage: 120/240 Volts AC
  • Interrupt Rating: 10 kAIC
  • Mounting Mode: Bolt-on
  • Wire Size: AWG 8...AWG 2 Cu/Al
  • Tightening Torque: 44.3 lb-in
  • Dimensions: Height: 3.1 in; Width: 2.2 in; Depth: 2.9 in
  • Weight: 0.800 lbs
  • Certifications: UL Listed, CSA

This Square D QOB340 bolt-on circuit breaker provides reliable 40A, 3-pole overcurrent protection for 120/240V circuits in QO loadcenters and NQ/NQOD panelboards. Featuring thermal-magnetic trip and VisiTrip indication, it delivers durable performance and enhanced safety for commercial and residential applications.


New Condition

  • Products in new condition are unused and in their original state.
  • Backed by our 24-month warranty, ensuring reliability and peace of mind.

Reconditioned Condition

  • Products in reconditioned condition are previously owned but have been professionally tested and inspected to ensure full functionality.
  • May include minor repairs, such as replacing damaged screws, but are not fully refurbished.
  • Covered by our 12-month warranty, guaranteeing performance.

Free Shipping on Orders Over $250

Enjoy free standard shipping on all orders over $250!

  • Applies to the contiguous United States
  • Excludes Alaska, Hawaii, U.S. territories, and oversized items
  • No promo code needed—free shipping is automatically applied at checkout when your order total is $250 or more.

For full details, please refer to our Shipping Policy.

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  • Free returns within 30 days of purchase
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