Product review (3 stars): i don't think these are actual humidiwick brand...
these lack the metal filaments the humidiwick brand has, & they suspiciously arrived in just a clear plastic baggie in the cardboard box. No box.
so, i do not think they are actual humidiwick (which i have used for years & work just fine), unless humidiwick has changed their filters physically.
  however, they do fit just fine in my humidifiers.
the reason i am giving only 3 stars is b/c i ORDERED & paid for humidiwick brand filters, not knock-offs & there is absolutely no reason for me to think that humidiwicks are what i received.
  will update after i have continued to use them, to let people know if they work as well as humidiwicks do.