It keeps your reeds from drying out very well and fits perfectly in my Daddario reed case. You can also store your reeds in a sealed plastic bag and put this in, it will do the same job. Although it dries out in 2-3 months and you will have to change it, especially If you don't close the reed case often or if the case is old and lets in the air. But for the affordable price, I say it's worth buying, I usually buy more than one at a time, they don't dry out until you open them.