Nearly everything can be adjusted. The back can lock into multiple settings including straight up. The armrests can go up and down back and forth and can turn inward or outward. At 6'2" this is one of just a few chairs that can sit tall enough for me at its highest. With all those positives the are only two things I don't like. Each side of the seat has a spot where the cushion angles up by the armrests. This can be a bit uncomfortable. The straps of the top pillow for the headrest are not adjustable and it kind of droops down so the pillow hits at back and neck instead of neck and head as I'd prefer.
I bought this for my autistic teen son who loves to use the computer. I did not attach the arms and it still looks good. I love that the hardware above the seat is all encased and the lumbar support pillow is heaven on my own back. I locked the back into a comfortable upright position and the back remains in position even when he tries to rock it back with his body weight. I am very impressed as he is very rough with chairs! I spent a little more than I originally intended with this but it is so worth it.
I love height adjustment are adjustment and able to adjust seat to what ever height I need. also back rest is great and adjustment is easy for relaxing. Great Chai