Mid spinal support with memory foam promotes neutral posture Lower lumbar support with three memory foam sections conforms comfortably to your lower back Tri-Tachment system eliminates the need for readjustment Memory foam responds to back weight and warmth for custom support Professional back support allows for optimal working comfort. A 2-tiered support system features a mid spinal support for good posture, and a lower lumbar support that conforms to natural body curvature. Tri-Tachment system eliminates the need for readjustment. Memory foam cushions self-adjusts for custom support. Fits most office chairs.