A drop-in replacement for older Zinsco and GTE Sylvania load centers, the Q243020 restores safe power distribution without requiring panel modifications. This 3-pole, 20-amp molded case circuit breaker features a distinctive red color-coded handle for quick visual identification. Rated for 10kAIC at 240VAC, it utilizes proven thermal-magnetic trip technology to defend commercial circuits. It serves as an exact-fit alternative to the UBIZ243020 substitute breaker.
What load centers are compatible with the Zinsco Q243020 circuit breaker?
This breaker is designed as a direct plug-on replacement for older Zinsco and GTE Sylvania load centers that accept Q-series breakers.
Is there a modern aftermarket replacement for the Q243020?
Yes, the Connecticut Electric UBIZ243020 is a newly manufactured, exact-fit substitute for this 3-pole, 20-amp Zinsco breaker.
What does the red handle on this Zinsco breaker indicate?
Zinsco utilized a color-coded handle system for quick visual identification during maintenance. A red handle specifically denotes a 20-amp rating.
How many panel spaces does the Q243020 require?
As a 3-pole breaker, it requires three standard spaces on the busbar of a compatible Zinsco load center.
Can I install the Q243020 in a modern Square D or Siemens panel?
No. This breaker features a proprietary plug-on clip design that is strictly compatible with Zinsco and GTE Sylvania busbars. It will not fit panels from other manufacturers.
Are there known safety concerns with legacy Zinsco panels?
Yes. Zinsco equipment has a documented history of reliability issues, including breakers failing to trip during overcurrent events and poor busbar connections that can cause arcing or overheating. Many electricians recommend full panel replacement when feasible.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 47 reviews.
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Reviews Summary
Generated by AI from 91 most recent customer reviews
Last updated 8/1/25
Customers say these circuit breakers arrive quickly and match their specifications perfectly. Many reviews mention success finding hard-to-locate specialty breakers through this supplier. Common feedback includes praise for the accurate product descriptions, reliable shipping, and competitive pricing. While some note occasional stock limitations, users consistently report the breakers fit and function as intended.