I am so happy with this AC, I'm going to buy another one. It's quiet and cools quickly. The app works smoothly. Our window only has to open about 4 inches to accommodate it. They include this strong foam to fill the gaps on either side. At first, I thought it wouldn't fit our window since it has wide lips on the inside and out, and when we unscrewed the metal supports to secure it, the supports fell out. We did it again and were able to make it stay.