I have an old Kaywoodie that I really enjoy. It has the stinger as shown. My question is: What is the purpose of the round ball on the end? It has 4 holes in it (you can only see two in the picture, but two more are on the underside). The ball is hollow and the 4 holes all interconnect. What they Do Not do is add anything to the draw. The only hole that draws at all is the larger hole that my pen points to. The narrow tapered part of the stringer appears to be solid.