Product review (5 stars): Seems silly to buy these but they really work. ...
Seems silly to buy these but they really work.  I used mine for an entire month without getting that nasty residue I usually would see within a week in my humidifier without it.  Frivolous, yes, but I don't care. Some things are worth the convenience with the amount of frequency i use my humidifiers.  I will certainly buy them again.