For inner-duct diameters from 71 up to 315 mm. Diameters above 315 mm only available for very sturdy or double-wall ducts for which tightness and stability cannot be guaranteed.
The unique Allen screw (M6) to be tightened shortens the assembly times drastically. Easy disassembly (unlike the plug-in system).
On a 100 mm Ø plain duct the necessary force to pull the connection apart is ≈ 1100 N (humidity and dirt can negatively affect these values). When installed vertically, each duct segment must be individually fixed and secured.