Product review (5 stars): These are awesome, I have two of the model 350 humidifiers ...
DON'T BUY THE JUNK OEM FILTERS! These are awesome, I have two of the model 350 humidifiers and the old filters would drain a tank every 24 hours. These are much thicker and empty the tank in 8-10 hours depending on how much the heat is running.  Our house is significantly more comfortable now. Don't question the generic packaging, these are much better than the Honeywell branded filter.