Bionic segmented spine-fitted backrest, highly fitted to the curve of your spine High-density rebound sponge, made of environmentally friendly materials, with strong rebound, skin-friendly and breathable fixed elastic waist support?triangle armrests Elastic mesh, breathable, wear-resistant and dirt-resistant headrest adjustment?4cm height adjustment 90°-125°backrest tilting Electroplated steel five-star feet?hydrostatic bearing800kg Silent and smooth PU wheels, wear-resistance 360° rotation, free height adjustment, universal casters Seat size?50cm Seat depth?46cm Minimum seat height with the gas rod at lowest position?42cm Maximum seat height with the gas rod at highest position?50cm Backrest height?59cm