The high quality materials and elastic foam make the perfect outlook, which gives continuous supports to the lumbar vertebra under every movement of the body. The precision synchronized mechanism makes the back and the seat move about relatively at the same time, so as to provide relevant support to the body whenever it moves about; Reduce strain on muscles and the vertebrae, thus promote the blood circulation and relax both the body and mind; Yet helps to alleviate the tiredness of the upper part of the personnel who has to bends over his desk long time. Components details 1. Seat cushion---high elastic mold foam with leather cover. 2. Back ----high elastic mesh fabric (taiwan mesh18-b, standard). 3. Caster---n50r nylon castors. 4. Base---polished aluminum base. 5. Mechanism---multi-function synchronized mechanism. 6. Armrest----1d armrest with leather cover. 7. Gas lift---chromed plated, 100mm range. 8. Back and seat support---chromed plated aluminum support. 9. Lumbar support---high quality black fabric and high elastic foam, height adjustable. 10. Headrest--- height and angle adjustable, leather cover, chromed plated aluminum support.