CONTOURED CUSHIONS FOR AN EXTRA SUPPORTIVE TASK CHAIR. For a task chair with a little bit more support, check out the HVL220. The contoured seat and back provide extra support for long lasting comfort, and the adjustable height arms accommodate many different sized users. A B A. MID-BACK WORK CHAIRHVL220 Dimensions: Width - 20˝ Depth - 16 3⁄4˝ Height - 41˝ B. PNEUMATIC LIFT Raises and lowers chair to achieve best relationship to work surface.