These highly polished solid metal flip over tops have a chrome like finish and are excellently machined. Simply spin it as normal and watch it suddenly flip over and then continue to spin upside-down.
Flip over tops (often known as tippie tops) were originally invented in 1950 by the Danish
engineer Werner Ostberg. His inspiration came from a visit to South America where he had
seen local people playing with a small round fruit. When they turned it by the stalk like an
old-fashioned spinning top, it would spin for a second and then invert and spin on the stalk.
However credit should be given to Helene Sperl who in 1891 patented a "Wendekreisel" in
Germany. The patent ran out and it was never mass produced.
More information about the history of this product can be found here https://fysikbasen.au.dk/English.php%3Fpage=Vis&id=79.html
The tops are 29mm in diameter ( 1.14 inches )
and about 36mm tall (1.41 inches )
The barcode for this product is EAN 506018806000