Apr 15, 2021 - 09:46 AM
The main difference is for the pro shop to have a few more drilling options. With the 3 to 4 pin it enables the pro shop to have more flexibility with the layout.
We have a great selection of articles also on drillings - https://www.bowlersmart.com/2020/08/21/drilling-performance-bowling-balls-pro-t
Thanks for your question.