The Helios FSD 160 is a robust flexible duct made from aluminium casing. Its perforated inner surface holds a mineral wool lining approximately 58.5 mm thick, providing effective noise reduction. The duct has spigots on both ends for easy connection to other ducts or for secure attachment to fans using a pipe clamp connector (BM). This duct exhibits a pressure drop about four times greater than that of comparable rigid ducting.