An icon for the "Accordion" switch on accordions. A commonly seen version that represents the two middle-pitched reed ranks with symmetrical offset dots, even though one of the ranks is the natural-tuned "clarinet" or "clarino" rank that's otherwise represented by a centered dot in combinations without the sharp-tuned rank.
Modified version of https://commons.wikimedia.org/wiki/File:Accordionstops_master.svg
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