Looks like a hanging flower pot without the chains. The holes in the bottom are for drainage.This is a hilarious German eBay auction for a so called "old synthetic hat block for milliners - round 56 cm".
Ofcourse it is complete nonsense ... I know exactly what it really is
Who else can recognize the true purpose of this "poor man's hat block" ?
https://www.ebay.de/itm/alte-Hutfor...sh=item5b4badf4c3:g:NIUAAOSwtlpamr1T#shpCntId
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