Through extensive press testing with the Zero and other presses, we've learned that the most consistent sizing comes from direct contact between the shellholder and the die. However, this setup typically limits your ability to adjust your shoulder bump. The new Zero Modular Shellholder System changes all that. Now, you can easily set up your shellholder to match your die, allowing for precise adjustments while maintaining consistent sizing. This system offers enhanced consistency, repeatability and ease of use minimizing hassle while maximizing performance. It's a win-win-win solution for reloaders seeking precision, flexibility and reliability in their setup.