Remarkable for style, comfort, and support, Sift task chairs have all-mesh seats and backs made from SoSoft mesh - a breathable, supple, and incredibly soft woven material. The constant cooling effect of Sift's mesh ventilation promotes a more comfortable and productive work day. SoSoft mesh has a 10-year warranty and passes KI's rigorous testing for bursting, tearing, and cleanability. The built-in lumbar mechanism offers enhanced comfort and constant support. The mechanism adjusts easily from a sitting position. Catering to individual seating preferences, the full-function task chairs offers synchro-tilt, seat slide, and back lock and has been tested to support 300 pounds. Task chair is available armless or with adjustable T-arms.