The purpose of a headrest is fairly self-evident – support the head. Support may be necessary while performing simple and repetitive tasks where the head barely moves.
Adjustable Lumber support
Regulates the height of lumbar support independent of the seat back. Easily adjusts to enhance comfort. Benefits: The lower (lumbar) region of the spine should generally have an inward cure (lordosis).
Tilt Tension control
The 'tension' feature is a knob which can be adjusted to increase or decrease the force needed to tilt. So, a tension tilt feature essentially allows you to decide how much you want to recline on a chair, and how much force is needed to do so.
Adjustable Armrest: It's using a lever system you can see this one isn't as easy to make adjustments with but you're able to move them up and down by loosening the lever on the back.