I'm surprised Eric Fogel answered you.
This radio is one of several GE radios nicknamed "atomic" by collectors for the symbol on it, just as he told you. An even more popular GE "atomic" model is the model 861/862 series (as seen on "Leave it to Beaver").
He's been known to describe his radios using keywords that will bring out buyers, and has done very well doing so. The Zenith reference was just a remnant of the template he used to update an old listing to this new one so he doesn't have to keep typing a lot of the same text for each listing. He's been selling radios on eBay (for often fantastic sums) for years, and has a very loyal group of deep-pocketed buyers.
To view some of his past sale successes, check out his feedback page.
http://feedback.ebay.com/ws/eBayISAP...edbackAsSeller
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