FLEXIBLE PVC DUCTING- Applied hard-wearing, flexible vinyl woven polyester with carbon wire spring and adhesive tape, smooth inside wall. Designed to be super flexible and flame-retardant. ROPES ADJUSTABLE- Thick ropes can be adjusted to fit the duct' mouth size, ensuring a good-sealing environment and high woking efficiency. D-SHAPED RINGS- D-shaped rings are set for hanging the ducting freely. Two stainless steel rings plus 4 D-shaped rings of two meters for one ring. REINFORCED DESIGN- Wear resistant professional industrial adhesive tape and thickened high carbon wire spring ensure rings to be practical and durable. WIDE APPLICATION- Our heavy duty 8 inch duct designed for ventilation applications includingduct fans and vent exhausts in factories, basements, farms, chemical, tunnel, automobile manufacturing, ect.