Have you seen a device which rotates and mostly held in hand?
Yes that is spinner. This is now Best Selling toys in Amazon and any other online selling platforms.
Every household now necessarily has it. And owning as many as possible is what most children want.
This roughly gives idea how big is its market.
And children are going nuts to get it. One who already has too is engaged seeing videos on youtubes.
Important thing is they are not cheap. Damn! expensive.
Market of Spinner is ever growing. People say rotating it will help reduce stress. While some of us might be spinning for tenson relief world is going crazy on getting one.