Cutler Hammer has their "Classified" series of circuit breakers, that are designed to replace the 1" width SqD Homeline, Crouse Hinds, GE, Siemens/Murray, and T&B breakers.

They also produce a 3/4" version, designed to replace the SqD QO series.

https://www.platt.com/CutSheets/Eaton%20Distribution/Breakers-ClassifiedType.pdf

Note that they aren't UL listed, but UL Classified.

I think the BR is only listed for use in Cutler Hammer panels.


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