THERABAND Standard Fitness Balls are offered in the following sizes: 55 cm, 65 cm, and 75 cm. These values indicate the diameter or size of the object after fully blown. Our high-quality exercise balls have become ideal for clinic and at-home usage, and are fantastic for balance and posture exercises, muscle toning, meditation, and Gymnastics. The non-slip, latex-free PVC polymer composition is suitable for reclining, sitting, or kneeling on while working out the core, lumbar, shoulders, and calf muscles.