Opening device for the inflow of air made with a fixed frame in extruded aluminum profile, natural color or silver anodized, buffered with blind blades in extruded aluminum, natural color or silver anodized. The fins are inserted in a movable slat holder connected to a pneumatic piston equipped with an opening and closing block in order to avoid manual opening of the slats or alternatively to a 24V low voltage electric motor that can be connected to an SVM control unit or SV-ds by means of a LIP model interface module. At the base of the frame there is a fixed-type stop plate that prevents the infiltration of rainwater to the foot. A special fixed type slat, positioned in the upper part of the frame, compensates for the measures constrained by the section of the slat, making the device adaptable to any height measurement.