They work. We have had issues with our cats going to places that should be off limits (mostly safety). Before people get upset, we take in strays and recoup them and adopt them out, so we have a lot of cats (50 ) and some are not keen to behaving at first. They are sturdy, unlike others that can bend and break off. Our cats of course don't like them. They have been doing their job and keeping them off of places that we have installed them. I have installed some outside and possums don't like them also😈. We are going to get a couple more boxes of them to put in other places and outside.