The stainless steel upgrade kit for the Hario Skerton coffee grinder produces a better, more consistent course grind by centering and stabilizing the lower burr. It installs with only a screwdriver. There is no need to remove the lower burr from the center shaft with this kit. This manual grinder works great for finer grinds, but if you want to use a french press or some other brewing method that requires a consistent course grind, this upgrade kit is a must. It greatly improves the consistency of courser grinds by keeping the conical bur centered, resulting in an even gap between the two burs. This even gap is what produces a very reliable and consistent grind.