Chair with aluminum swivel trestle base on glides. Seat with built-in self-tensioning weight response mechanism, backrest with 3-position recline, adjustable lumbar support breathing up to 60 mm. Low backrest with visible backshell (available in black or white), and front in polyester mesh in matching color. Seat upholstered in leather, customer's leather, coated fabric, fabric or customer's fabric. Fixed or 2D adjustable armrests in nylon fiber, color matching backshell, are available upon request and with a surcharge.