Product review (4 stars): these filters work fine. I kinda have to stuff them into the ...
I used these before.  They are aftermarket, and not made specifically for my humidifier.  (My humidifier is so old I am not sure I can still buy the original filters.)  However, these filters work fine.  I kinda have to stuff them into the filter cage, but once in, they do the job.  I keep these on my shopping list to buy another set each year when it is time to set up the humidifier.