Studio Designs Ergo Pro Chair in Black 18409 Overall Dimensions: 23"W x 22"D x 33.75" - 50"H Professional Drafting Chair, Pneumatic Height Adjustment, Drafting Seat Height: 28.5"-32.25" Can be Set as Task Chair without Foot Ring Insert, Task Seat Height:17.5"-20.75" Five Star Nylon Base with Casters for Mobility, Adjustable Seat and Back Contoured Padded Seat and Backrest, Adjustable Chrome Foot Ring Overall Dimensions: 23"W x 22"D x 33.75" - 50"H Professional Drafting Chair, Pneumatic Height Adjustment, Drafting Seat Height: 28.5"-32.25" Can be Set as Task Chair without Foot Ring Insert, Task Seat Height:17.5"-20.75" Five Star Nylon Base with Casters for Mobility, Adjustable Seat and Back Contoured Padded Seat and Backrest, Adjustable Chrome Foot Ring