good selling full mesh breathable ergonomic chair midback chair lumbar support chair 2017 factory supply ergonomic chairs offer fuller back support, and with the right ergonomic design, can be sat in for a four hours at a time or longer. High-end chairs in this category, such as this fully upholstered by mesh design chair # B-1800A, are comfortable for long periods of seating. Details: Material of products: Polished Aluminum, Nylon, Mesh Materails of Armrests: Aluminum + PU with Chrome Material of base &Caster: 350mm Aluminum Base,60mm Nylon Casters with Chrome Mechanism: Multi-function Aluminum Mechanism/Tilt-Tension and Angle Lockable/Sliding Seat Product Dimension: H115-123.5*W60*D45-50CM N.W./G.W.: 21.5KG/25KG Carton Size,Packaging: 70*58*49CM, 1PCS/CTN Quantity per Container: 310PCS/40HQ