... proof flexible ductanti-static ventilation duct, air duct, anti-static flexible ductflexible duct:/air duct/exhaust duct,ventilating duct,flex duct, ventilation duct1,Material: PVC ... oleic acid, harmful liquid state gas ect. the duct body is without any lapping defect,with the ... :Widely used in these working environment such as tunnel,mining, basement, ship building or welding, laboratory , engine ...