This holder goes on the outside of your balcony door, so it holds the door shut when you are outside, thus preventing wind from coming inside.
You can fasten the holder with screws or double sided tape. The handle part is made out of two parts, the clip and the handle it self.
This is made because if the clip brakes during install, you can print another one, after you have inserted it, put a bit of glue in the hole of the handle and push it onto the clip.
The author marked this model as their own original creation.