I don't recall using any of these, there should be 24. I just didn't count them. If you wanna get your Balls of Fury on or prep for the Olympics you're gonna need these.

https://www.amazon.com/STIGA-1-Star-Table-Tennis-Balls/dp/B01BNJZYZM

Pictures:
https://photos.app.goo.gl/Z3V7czobrRyn1Ms66