The window feature is so you can cut it out to place over the middle box area and maybe have a hidden message on your robot, if that makes sense at all. I made a robot, glued the window on, glued the original shape inside and put a heart inside. I hoep this makes sense. I also cut it at the same size - I cut a 4" robot and left that as my setting to get the right size window. If you had not asked this question I would have missed the window feature so I was curious and had to go check it out. Thanks for the great question and awareness you brought because of it.

I just purchased this wonderful cartridge and wondered about the window, too. The earlier suggestions occurred to me while musing, but also it would be cute to make some little paper gears and make it so you could open the window and look "inside" the robot. Would love to see Cricut do a Steampunk cart with gears and all the trappings of that wonderful genre. The Robotz cartridge could have so many uses in tandem with that theme! (as well as the Halloween, Over the Hill and any Victorian-themed cartridges-just sayin')