Hubcaps. At least to me these things meant either old cars, cheap cars or ricer cars (spinning caps). However, Formula 1 teams bring them back to the scene. First Ferrari. Then McLaren. And finally some other teams adopted this. Of course in Formula 1 things are done for some kind of purpose. In this case hubcaps help cooling brakes.
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Chapel added some more cool
— f1vladChapel added some more cool material:
And some links: