The Topstar Open Point SY office chair is perfect for the workplace Everything you need to know about the backrest The mesh backrest ensures good air circulation so that you can stay cooler in summer. You can adjust the angle and height of the backrest to ensure you are always comfortably seated. Making your future work even easier The synchro mechanism ensures a dynamic sitting position. The seat and backrest work synchronously together and in a fixed relationship to each other. This ensures optimum adjustment to your posture and needs.