You can lean back with perfect balance, as the tilt tension mechanism automatically adjusts the resistance to suit your weight and movements. You sit comfortably since the chair is adjustable in height. Your back gets support and extra relief from the built-in lumbar support. The safety castors have a pressure-sensitive brake mechanism that keeps the chair in place when you stand up, and releases automatically when you sit down. The mesh material of the backrest lets air through to your back during long sitting periods. The castors are rubber coated to run smoothly on any type of floor. Increased stability since the tilt function is lockable when the backrest is in the upright position. This product requires assembly #cheapikea #fastshipping #goodpackaging