Blauberg Primo 400 Mixed Flow Inline AC Fan - 400MM (16" Inch) | 3 SpeedThe Blauberg Primo 400 Mixed Flow Inline AC Fan 400MM is built for serious commercial ducted ventilation. Pushing up to 3350 M3 H through 400MM (16" Inch) round duct, it suits large amenities, plant rooms, warehouses and commercial kitchens that need strong, reliable extraction or supply air. A 3 speed AC mixed flow motor lets you balance noise and performance on each job, from low speed background ventilation through to full power when you need to