When the wise person says the eyes are the windows to the soul, he has not just pointed out the importance of sight, but also of the strategic position of a window as the entrance to discovery and you get best and quality Invisible grille for cats.
Thieves do have their initiatives in getting into a building or a business structure undetected.
Even modern jail facilities today don't put up windows, or if they do, they have to be so high from any person's reach so that escape would not be made possible.
So why would anyone try to live like the imprisoned life by having unused or no windows at all?For the sake of security, yes, people put up fences and invisible grille for cats around every manner of entrance in their establishments.
Good thing that there are now companies that manufactures and sells invisible window grilles and you can get these at best as well as Invisible grille price.
This aspect of invisibility is truly a plus factor since this provides a strategic protection for the dwellers.