The window design developed by ACTUAL looks as if it was created out of a single piece. The shape of the window is cubic and angular, uncompromising in its design without slants, glazing beads or optically disruptive joins. Sash, frame and glass are flush on the outside and the sash and frame sit flush on the inside as well. The interior flush-fitting view is highlighted by the concealed fitting of invisible hinges. The minimalist sash profile allows for very narrow visible window frames.