The manual coffee grinder can be adjusted to three levels: coarse, medium, and fine by turning the adjustment wheel clockwise for fine and counterclockwise for coarse. Make sure there are no obstructions between the internal and external ridges. Turn the adjustment wheel. This is very important when switching from coarse to fine. Professional ceramic burning will not burn your coffee beans, making the grinding process more detailed and the coffee powder more homogeneous. It maintains a rich and innovative aroma for better coffee flavor. This small manual grinder can provide the fresh coffee bean experience you want - feel the grinding of coffee beans as you grind them manually! Enjoy the refreshing aroma of your daily coffee while preparing it with your espresso machine. Ground, brewed, and enjoyed.