Product review (5 stars): Stops reed warping
I really like this case.  I live in the Northeast, and in winter, the air is very dry inside due to heating. Typically when I pull out a reed to play (especially larger ones, such as tenor and bari), it will wrinkle up on exposure to moisture. I then have to put up with it until it flattens out again.  This case seems to keep the reeds moist enough to avoid this issue.