I had to do some searching, but I found this about standard Seimens breakers

"Will replace American Switch, Westinghouse Type BR, Bryant, Challenger, Sylvania, Crouse-Hinds, Murray, Frank Adams, General Electric (Full size only), General Switch, I-TE, Gould, Montgomery Ward and Sears. U.L. Listed"

So it looks like Siemens is good for just about any common "knife" style plug on panel except Sq D Homeline.