... air duct Light weight Oil,Acid,Alkai&high temperature resistant&fire-retardant PVC Good price,fine quality,satisfying service Air duct ... color: yellow,red,orange .white,black,green ect.5,Character: enduring high temparature,acid,alkali,oleic acid, harmful liquid ... laboratory ,air-conditioner,engine room, the municipal conduct engineering,fire-fighting to ventilate or exhaust waste air,dust to supply ...