Product review (1 stars): Did NOT fit as represented
The caps did not fit the bottles on my Bemis 497-300 humidifier.  They looked like they would fit but the thread size was wrong.  The caps I was sent had four crenelation-gaps around the edge, whereas the ones on my unit (and the ones in the photo) only have two gaps or notches.  I contacted the vendor and was told that they "should" fit.  Ultimately I had to return these and order from another source - and those did work.  The vendor did give me a full refund but I was out the cost of shipping back the misrepresented item.