I have around 6 squirrels that visit the feeder though one chooses to hang upside down on the one for the birds.
https://www.youtube.com/watch?v=7M4bUqyXYZM
https://www.youtube.com/watch?v=q_XaJPHG8Dc
https://www.youtube.com/watch?v=Uk7VY_f5AHU