Chair with 5 way swivel base on castors (for hard floors, in the same color as the base) in polished or lacquered aluminum, fitted with gas-lift mechanism for height adjustment. Exposed backshell and seat with built-in self-tensioning weight response mechanism, low backrest (H 90) with 3-position recline, adjustable lumbar support breathing up to 60 mm. The shell is available with front face upholstery backrest in nylon mesh in the same color as the exposed backshell (black or white) and seat upholstered in leather, customers leather, faux leather, fabric or customers fabric;with backrest and seat with front face upholstery in leather, customers leather, faux leather, fabric or customers fabric or with full upholstery in leather, customers leather, faux leather, fabric or customers fabric. Fixed armrests made in nylon fiber, in the same color as the backshell or as the underseat cover (black or white), or with different upholsteries for seat and backrest are available upon request and with a surcharge.