We have two tall skinny windows, one on each side of the front door. We have a very reactive dog to any movement seen outside. In a impulsive move to help her, I bought this, and I'm not disappointed! I was nervous at first because I didn't want to mess it up, but honestly this stuff is fool proof! It's so easy to install. I was worried that it wouldn't let in as much light in the entry way, but it's the same as before, but you can't see through it. You can see a blurry image of someone is standSee full review