Disclaimer – We use what we think are absolutely the best USA Made Suction Cups for the Kitty Cots that we sell made by Adams Manufacturing. That said, the nature of suction cups in general is that they occasionally disengage from glass surfaces. The best thing you can do as the owner of your Kitty Cot(s) is to daily check and make sure that the suction cups are well secure on the glass. It is up to you to check the suction cups regularly and replace them if they have extensive wear. We accept no responsibility for injuries or damage to windows, pets, animals, people and things and you agree you are using Kitty Cot(s) at your own risk. If you are concerned about mounting the Kitty Cot(s) on your window(s) for ANY REASON even Window Warranties then buy or use a different Cat Perch that does not mount on windows with suction cups. If you are at all concerned about any of this, we recommend you buy a different product. Thanks and Enjoy!