A 10 inch 78 rpm Harmony Disc Record record I found at a antique store. It has a larger center hole: larger than normal records and Standard Disc Records but smaller than a regular 7 inch 45 rpm record. I show different center hole size records for comparison.
Some of what the label says: \"Harmony Disc Record, Great Northern MFG Co. 147-153 Fifth Ave. Chicago, ill, U.S.A. ... A212 (3530)\".
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