Product review (4 stars): Works
There are no magic bullets when it comes to filters for humidifiers. If you flip the filter every time you fill the tanks these filters will last longer. During the driest times of winter you can get about a month to month and a half out of one of these. That is a lot from a filter. If you do not flip then you can cut the length in half. I am happy with these filters. To also help get the tank cleaners that come two in a pack.