If you are using the stability cushion on a chair, we recommend you use the cushion for 15-30 mintues at a time, repeating at regular intervals during the day. Adjust the amount of air in the cushion to increase or decrease the level of instabiltiy to suit. This cushion has one side fitted with nodules for foot massage and sensory work as well as providing extra grip whne used for posture work. The other side is smooth with small anti-slip dots, which some may find more comfortable when used as a seat. The cushion has a slightly sloping edge, which reduces the surface area in contact with the user, increasing the degree of work required to maintain the correct posture and thereby enhancing the benefit of using the stability cushion.