Because the lumbar cushion is pre-shaped, it gives the right support to the lower back while sitting. This gives you more comfort while sitting. If you use a lumbar cushion, it is nice that it stays in place, so that it can continue to provide the right support. The VITILITY Lumbar Cushion has two straps at the back with which you can attach the cushion to the chair. Because the straps are adjustable, it fits on different sized chairs. The lumbar cushion can also be used to improve your sitting posture.