flexible duct 1,fire-retardant PVC material 2,competitive price,fine quality 3,Oil, Acid, Alkai & high temperature Resistant flexible duct:/air duct/exhaust duct,ventilating duct,flex duct, ventilation duct1,Material: PVC flam-resistant static-free fabric with steel wire reinforced.2.PVC Thickness:0.3mm-0.45mm.3,Diameter:4" to 60" stander length:5m or 10m4,Main color: yellow,red,orange .white, ...