What breakers are compatible with a Cutler-hammer?

Breakers compatible with a Cutler-Hammer panel depend on which Cutler-Hammer panel type you have, because BR and CH families are not interchangeable. For a Cutler-Hammer BR panel, which is the most common one inch wide black handle type found in millions of homes, compatible breakers are Eaton BR, which is the current brand name for the same product, Cutler-Hammer BR for older stock, and also Westinghouse BR and some Bryant BR breakers because Westinghouse and Bryant BR designs were consolidated into Eaton BR. Eaton CL classified breakers that are marked as classified for BR panels are also compatible. For a Cutler-Hammer CH panel, which is the 3/4 inch wide tan handle premium line, compatible breakers are Eaton CH, Cutler-Hammer CH, and some Eaton CL classified breakers marked for CH. You should not use Siemens, Square D, GE, or other standard brands unless they are specifically UL classified as CL for your panel, as standard breakers from other brands will not have correct bus contact and violate code. The safest approach is to use Eaton BR for BR panels and Eaton CH for CH panels, matching amperage, poles, and whether you need standard, GFCI, or AFCI protection. Always check the label inside your panel door for the list of approved types and when in doubt consult a licensed electrician.