How does a yo-yo ball spin as fast as a formula car engine?

The balance design allows the yo-yo ball to be thrown and returned smoothly. Meanwhile, the yo-yo ball can rotate online for a long time without slowing down.To do this, the yo-yo ball has an ingenious device smaller than a penny inside. Between the inner and outer rings, 10 small steel balls roll together to block the friction between the inner and outer rings.Although the rope is wound around the outer ring, the inner circle can still turn at full speed, as fast as a formula one car.