With built-in box

Some of the advantages of this model are the optional built-in roller screen against insects, extra acoustic and thermal insulation of the container box and reduced energy expenses due to another important factor – during the installation of the operating mechanisms, the window frames are not drilled through. Another advantage is the easy-to-reach revision opening, placed on the inner side, for easier access to the whole mechanism. The lifting/lowering mechanism can be crank, motor or hand-operated.