50's Olds guys a little help

50's Olds guys need some help how are these wire wheel covers are attached with the lug nuts


photo from a car show


the mounting ring holes are Larger then the Lug nuts
anyone have a photo of the parts that are missing
or know many total pieces are there?

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stamped steel inner mounting ring holes are larger then the lug nuts
my question is what is missing a washer for each hole or ?
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Here are my 53 Buick wire wheel covers & heavy steel adapter which has 3 smaller mounting holes

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Total of 4 pieces - you can see the 3 small holes at 11, 1 & 6 o'clock
Buick uses bolts not lug nuts they hold the adapter on the rim the 2 large hold pas over the bolts
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