The best value for a quality mesh chair in the industry. The only mesh chair in the world constructed of solid metal components. Unique breathable and expandable mesh material. Contoured mesh lumbar support. 2:1 synchro tilt control. Unique pivoting arms. Totally unique control mechanism providing locking capabilities and dual controls. Pneumatic seat height adjustment. Continual comfort. Heavy duty metal base with dual wheel carpet casters. Some assembly needed.