Very adjustable seat: undo four allen bolts and the top section slides up or down to adjust the length. Quick releases under the front and top of the seat independently adjust the angle of the back and base, and also let you adjust how much lumbar support there is. 
A channel behind the cushion draws cooling air through a vent hole in the small of your back, and out through a hole at the top. Choose from a foam cushion (in two pieces to allow the seat to separate) or an airflow cushion which adjusts for length.
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