Bearing spinner knob for 606 bearings

This is a knob to be used for various fidget spinner designs.
It should fit the standard 606 bearing (6 x 17 x 6mm).

I used it for my aproach to a bearing-in-a-bearing spinner ;)

You can find the details in [my fishpepper.de blog](http://fishpepper.de/spinner) or my [bearing spinner youtube video](https://youtu.be/GNSc2NC869o)