Hasn't worked
I got it to keep the moisture out of my portable radio earpiece.  It is a clear tube with several loops before the earpiece and the tiniest water drop will block the tube making it useless.  I have two earpieces so I alternate them and during a three day tour it sits in the bag.  It has yet to get the moisture out of the tube.  I don't know if it would work better with a hearing aid, but it has not worked for the earpiece.  Maybe it needs a week or so, but I was hoping it didn't.  I guess try it out its pretty cheap so it shouldn't hurt the wallet too much.
Rating: 2 stars