Can I change the upstem configuration?
The Stündenglass upstems are two separate pieces: the center upstem and the outer percolator shell. The shell can be separated from the stem by holding onto the shoulder above the threads and turning the outer shell counter-clockwise. You can choose to take one off of one side and leave the other on or, take both off or leave both on. It is recommended to periodically clean inside these stems for optimal performance.