This special cushion is the best seating system for a healthy back. Can be easily inflated or deflated to change firmness. When used regularly at home, in the office, or while studying, Original Pezzi® Fit-sit helps prevent back problems by promoting the use of the trunk muscles and encouraging good posture. The Original Pezzi® Fit Sit is ideal in preparation for group sports, proprioceptive exercises and equilibrium in postural gymnastics as well as rehabilitation in physiotherapy treatment of ankle pathologies.