43031 - BOMAR Portlight PASSAGE 419 x 241 mm outside dim. Very solid material, very valuable, very nice to look at, really makes a difference! But it is also very difficult and accordingly expensive. Unfortunately, the attachment is not really easy, since the frame does not have to be assembled after installation, but rather holds the entire window itself. As a result, the interior (upholstery / wallpaper / wood) cannot simply be redone or renewed, for example, without removing the window or letting it hit the frame. Not quite optimal. And I don't understand why the screen is outside and not inside. Suboptimal cleaning technology.