The 4x4 Series' ergonomic design keeps you in all day comfort. Look at all these features¿ pneumatic height adjustment, articulating seat & back, swivel tilt with tension control, adjustable height ratchet back, lumbar support, independent back angle adjustment and height and width adjustable arms. The 4x4 Series gives you a great chair at a great price. 4x4 Series is Perfect for: Workgroup Seating Management Seating Large Corporations Small & Mid-Sized Businesses