Product Name: Underground Mining Construction Ventilation Air Duct for Tunnel Using Model NO.: BH-D Certification: ISO, CCC Performance: Wearable Shape: Column Application: Tunnel, Mining, Construction Material: PVC Color: Yellow, Black, Orange Accessories: Neck Adaptor Trademark: Bohwa Transport Package: Woven Bag Specification: Dia. 150mm-2000mm Origin: China HS Code: 59119000 Product Description BH-DUnderground Mining Construction Ventilation Air Duct for Tunnel usingMain SpecificationItemSizeDeviationAir Duct Diameter (mm)150,300,400,450,500,600,800,1000-20000±6Air Duct Length (m)5,10,20,300±150