Features: Double-layer aluminum foil pipe with steel wire reinforced steel wire.It has good flexibility, durability and easy construction. It has the function of arbitrary expansion and universal transformation It is supported by spiral- high tension steel wire, with strong flexibility, good self-sustainability after straightening, and low resistance It is clean and sanitary, does not pollute the gas-, has high strength, does not leak, and is durable The direction of the air duct can be arranged arbitrarily during the installation process, which has no impact- on the decoration ceiling. Usage: widely used in air pollution, industry, household, central air conditioning, ventilation system-, subway- ventilation, semiconductor, toxic gas exhaust, textile, machinery fan ventilation, ventilation, oil smoke-exhaust, smoke- exhaust of cigarette- hood in electronic factory Specifications: Material: Double-layer aluminum foil pipe with steel wire Length:approx 2M/6.56ft 300CM/9.84ft 6M/19.7ft Inner Diameter: approx 100mm/3.94in Temperature: 80℃ Package Includes: 1PC Air Duct note: Due to the problems of lighting effects- and shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.