Chair with a 5 way nylon fiber reinforced swivel base (black or white) mounted on self-braking castors (in the same color as the base, with soft or hard tread). High backrest and seat upholstery both available in fabric, leather, coated fabric, or customer’s material. 3D nylon adjustable armrests (black or white) with TPU pads in two sizes are available upon request and with a surcharge. Mechanisms: - Gas-lift mechanism for height adjustment. - Built-in self-tensioning weight response mechanism and backrest with 5-position recline. - Up&down of the backrest with 5-position recline, breathing up to 2.1/2'' and built-in lumbar support. - Sliding seat with 5-position adjustment, breathing up to 2".