Compact and nice fidget spinner! I have printed diverse spinners from thiniverse, but they all are to big, or have not enough smooth edges for me, and I decided to design my own spinner. For this I used one 607 ZZ hybrid ball bearing in the center and three 608 ZZ ABEC 7 ball bearings. I also tried to make it with one 608 full ceramic ball bearing in the center, but it gives 2x less spin time. With 607 I can reach 4+ minutes of spin time.