Ergonomics is what we focus on Metz. We want to offer you proper support and extreme coziness with different kinds of adjustable function. You can experience extraordinary comfortability with seat and back synchronization and height adjustable backrest.We hope you can have appropriate gesture while working and also get fully relaxed when lying on the chair. 1.Synchronization: Synchronized mechanism in multiple locking positions, anti prevention safety function. 2. Seat Tilt adjustment: Tilt function allows the chair seat be adjusted in certain angle. 3. Height adjustable backrest. The backrest can move up and down. Let the users can adjust the height based on personal demands.