This is a really good Highback Top Quality Black Fully Adjustable Office Desk Chair in a size large 
The chair is a lovely looking chair with minimal marks. 
The chair is well padded on seat and back. The chair is  Seat, Back and Arm Height Adjustable. Seat And Back Tilt. Seat Depth and arms go back and forth and also there is a quick release Arm screw to widen them and all with a Lumber Back Pump
Plenty of functions and all the above work fine.
Max seat height is 62cms. Seat width is 55cms and depth is 50cms  New these are over £600