CSO air-intake ventilators are designed to protect the circular ends of gravity ventilation systems.

The fixed blades of CSO are mounted at the inclination of 45 degrees. The protective steel mesh 12,5×12,5 (for air intakes with diameter D ≤ 200) or 20×20 (for air intakes with diameter D>200) is mounted at the back side of the air intake. The frame and the blades are normally made of galvanized steel. Powder coating to any RAL color and special construction (stainless steel frame and blades or aluminum frame and blades) is possible on request.