This is a fun variation of a fidget spinner. A three outer-bearing spinner, the outer edge of each bearing has tiny studs, simulating the knurling effect. There’s no doubt that you feel the points of the studs, they’re sharp! However, it does give an interesting feel when spinning via a flick of the finger against the edge.
This is not recommended for children under 13, or people with sensitive hands!!
It’s officially called a KnurledTri-Spinner designed by CarryTheWhat, and it’s pretty neat.