Ventilation device

The ventilation device (10) comprises a frame (12), which has an opening (16), and a check valve. A recess is provided at the check valve, through which a holding element (22) extends on the frame. The check valve is adjusted depending on the applied pressure difference between a closing position, in which the check valve rests on the frame and closes the opening of the frame, and an opening position. The holding element is deformable between a mounting position, in which the check valve is mounted on the holding element, and a locking position.