air duct Light weight Oil,Acid,Alkai&high temperature resistant&fire-retardant PVC Good price,fine quality,satisfying service Air duct ... ,ventilating duct,flex duct 1,Material: PVC flam-resistant static-free fabric with steel wire reinforced.2.PVC Thickness:0.3mm ... , laboratory ,air-conditioner,engine room, the municipal conduct engineering,fire-fighting to ventilate or exhaust waste air,dust to supply ...