The Tunturi Gym Ball is an extremely versatile exercise ball or sitting ball for sport, work and leisure. Countless full-body exercises such as back or pelvic training can be performed with the gym ball. Treatments using an exercise ball are used in various forms of therapy such as back exercises, occupational therapy, physiotherapy, obstetrics, gymnastics for the elderly, etc. It not only serves as a fitness ball, but is also a dynamic seat and is often used as an office chair. Simply replace your office chair with the Tunturi sitting ball for a few hours and your back will thank you. This ball has a diameter of 90 cm. The Tunturi Gym Ball comes with an inflation pump and instructions with various exercises. The maximum user weight is 110 kg and it is suitable for body heights from 190 cm. Body size/diameter: Up to 155 cm = Ø 45 cm From 155 cm - 165 cm = Ø 55 cm From 166 cm - 178 cm = Ø 65 cm From 179 cm - 190 cm = Ø 75 cm From 190 cm = Ø 90 cm