I have some PVC Windows, and it's very hard to find hooks I found hooks which pinch the rubber join, but after fews month, the join keep the form and the wind can enter I found other hooks with sticker, but after few mounth, the stickers are dry and the hooks fall So I decided to design mine If you print this model, you have just to put a nail and one point of hot glue

you will be able to remove easilly the hook without any dagradation on your windows