Gravity overpressure damper made of extruded aluminum and standard natural aluminum fins, complete with sealing gasket in the fins for greater efficiency in closing and reducing noise. Designed to maintain overpressure or depression inside the room. Holes (for wall/duct installation) incorporated in the frame for fixing with screws/rivets. Maximum recommended air speed through the damper: 6 m/s. Maximum temperature of the air through the damper: + 80°C. Damper dimensions: 400x400 mm.