This is a barrier to prevent squirrels from eating the seeds in a bird feeder that is mounted on a pole. The hole diameter of the model (for the pole) is 15.5mm, so you may have to make an adapter to mount it on your bird feeder pole. (Try using foam tape.)
The model is a single wedge. It takes 6 wedges to make the entire barrier (see images). Use the side holes to temporarily bolt 3 wedges together to attach them together with glue.
Bolt the two half barriers together, around the pole, so that you can remove it from the pole, if necessary.