Chair with polished or powder-coated aluminum five star swivel base, mounted on self-braking castors (color matching with base) and equipped with gas-lift mechanism for height adjustment. The shell in white polypropylene is upholstered in fabric, leather, coated fabric, fabric or customer's material. Aluminium armrests are offered in the same finishes of the base. The optional armrests must therefore be included when placing the order, because they can be assembled only on compatible shells.