Inline sound- and heat-insulated centrifugal fans with forward curved blades and the air capacity up to 9540 m3/h. Designed for supply and exhaust  ventilation systems. Compatible for connection with rectangular air ducts with cross sections 400х200, 500х250, 500х300, 600х300, 600х350, 700х400, 800х500, 900х500, 1000х500 mm.