simple design desk chair task chair staff chair office chair 2017 hot selling There are multiple kinds of office chairs designed to suit different needs. The most basic is the task chair, which typically does not offer lumbar support or a headrest. These chairs generally cannot be sat in for more than a couple hours at a time without becoming uncomfortable, though they often offer more room to move than higher-end chairs. Features: 1) PP back frame and PP armrest. 2) injection foam seat cushion, enduring long time seating without deforming the cushion. 3) thick butterfly mechanism. 4) oblique over BIFMA three gas lift (black), no dust cover. 5) 310mm black nylon base BIFMA tested 6) 50mm dia BIMFA certified black + gray castors.