What is a, “Chi Ball”?
A Chi Ball, or Chakra, is from the Sanskrit word for, “spinning wheel,” referring to the spinning wheels of light within the energy body. (SOURCE page 205)
Describing a ball of Chi is impossible, so it takes imagery and willingness to accept the idea to understand.
FIRST, What is a ball of Chi used for?
Simple Answer:
It gives a focus to come back to so that you can train our mind to train itself.