I think that only the C-H "CL" type breakers are acceptable as substitutes for other brands unless it's listed in the panel's label. Some older panels (General Switch, Crouse-Hinds, etc.) that were not a brand that made breakers (siemens, SQ D, Cutler-Hammer, etc.) had a list in their label of acceptable substitutes. It goes back to the listing I think.I think BR breakers are listed as substitutes for Siemans. I have used them in such manner.