Flexing back is constructed of ilira®, a multidirectional stretch material that provides air flow and breathability. Fabric is soft and non-abrasive so it won't damage clothing. Height- and width-adjustable arms for a custom fit. Five-star base has casters for easy mobility. Recommended Applications: General Office & Task; Seat/Back Color: Fog; Features & Functions: Pneumatic Seat Height Adjustment; Seat Glide Mechanism; Synchronized Knee Tilt; Tilt Tension/Tilt Lock.