The helicoidal circular duct is a rigid, lightweight, seam-folded, galvanised or stainless steel tube which is smooth inside. The duct is considered to be female and all the accessories male, the latter fitting directly inside the duct. Sections are joined by means of sleeves.

We have ready for immediate delivery a wide range of diameters: from 150 to 500 mm in galvanised and between 150 and 400 in stainless steel. Thicknesses 0.5 to 1 mm. Supplied in 3 metre lengths. 15-day delivery for other diameters. We also have in stock the full range of standard accessories for every type of installation as shown in the following diagrams. Same diameters as the duct.