The term Yoga Tune Up® Therapy balls refers specifically to the original YTU Therapy Balls.
The Roll Model® Therapy Balls are all the various Therapy Balls used within The Roll Model® Method and YTU, i.e., the YTU Therapy Balls (OG’s), the Therapy Ball PLUS, the ALPHA Ball and the Coregeous® Ball.
Collectively, these are The Roll Model Therapy Balls.