This flexible duct model features thermal insulation based on 25 or 50 mm thick mineral wool.
The inner cladding is made of two-ply 30 µm polyester film. The outer cladding is made of
two-ply 30 µm polyester film with metallized finish. Between the inner cladding and the
insulation there is a polyester vapour barrier film.
The inner cladding is reinforced with a helical steel spring wire coil.
