Product review (4 stars): Works as well as the original
No matter what the original box says, no filter is permanent and forever! After a couple of years I was no longer able to remove all of the accumulated minerals from the "permanent filter" and this replacement makes our humidifier work like new. I never have mineral dust spewed throughout the room as some have mentioned, but I never use the appliance on its highest fan setting and I always add some distilled vinegar to the water. I would recommend this replacement to all who have a humidifier with a similar looking filter.