1) Integrated headrest (7 level height adjustable,3 level angle adjustable) 2) Backrest adjustment (60 180 degree) 3) Armrest adjustment (0 120 degree) 4) Lumbar support (air bag) 5) Lateral support (air bag or mechanical) a) PU or Cow top leather b) Mult-function mechanism c) Gas lift(50,000 lifetimes) d) Metal base e) PU or Nylon caster f) The castor, base, gas lift and mechanism have passed the certificate of BIFMA.