Some insurers won't insure Zinsco and FPE panels.

I write stab-locks and FPE panels with red on the breakers. I'm not so quick to write off everything else that's FPE, even though they're old.

source https://www.inspectorsjournal.com/topic/18831-some-insurers-wont-insure-zinsco-and-fpe-panels/?do=findComment&comment=172520