Gotta love Ninjas..... Too many plain Fidget spinners out there so customized with these covers. The middle button is slightly indented for better grip. The symbol is Japanese for "Ninja". These fit the 22mm bearing.

I used both http://www.thingiverse.com/thing:1803795
and
http://www.thingiverse.com/thing:1833143

for the main Fidgets Spinners.

Painted with Acrylic Paint and sprayed with clear lacquer.

Wanhao

Wanhao Duplicator i3 V2

No

Yes

20%