1)material:pu cover, chrome base and armrest2)castors: pu mute castors, one hundred thousand times friction3)sponge:high density sponge (24,28 30density,   flame retardant or not )4)board:have past strength test5) Our factory is with ISO9001 certification6) Our factory has the certificate of import and export7) The castor, base, gas lift and mechanism have passed the certificate of BIFMA.8) The chair with high quality and best price

9)port of delivery : shanghai

high quality office chair