Round duct (SPIRO) is very common in ventilation systems, and the grilles especially designed for such tubing are indispensable.
Round duct grilles, used for both discharge and suction, are the ideal solution for false ceilings. Available in two versions, RDD and RDR – for discharge and RDD1 and RDR1 for suction, they transfer the air without changing the pipe contour. Both single and double deflection tubing grilles are either easily bent at the frame (RDD, RDD1) – so as to follow the contour of the duct, or curved in the shape of the duct (RDR, RDR1).
The grilles are equipped with mobile blades, facilitating air circulation both vertically and horizontally.
Just like double or single deflection grilles, due to the wide free surfaces, they also handle large flows.


Round duct grilles can be used both in industrial applications (storage houses or halls), and in various applications where a surface mounting of the ventilation system is desired (stores, restaurants, bars, gyms or even offices). An apparent ventilation system distribution solution and the use of round duct grilles could lead to a significant decrease in the useful height of the rooms and a lower total height of the building. Easy installation is another advantage of the round duct grilles.