Product review (1 stars): Worked for a while...
A new pad stopped working after about 3-day use of my Slant Fin Germ Free GF-200 humidifier (8-9 hours continuously per day).  The humidifier was cleaned and all the mineral coatings were removed from water pipes and heating plate before the new pad was put in.  After 3 days, the water supply pipe outlet connecting to the heating plate of the humidifier was congested and totally blocked by mineral powders.  Very little water can go thought the powders to reach the heating plate, and even if the water gets to the plate it got heated and evaporates immediately much faster than new fresh water comes.  So, the temperature of the heating plate goes straight up.  Lucky, the humidifier is able to detect the excessive temperature and shut down the electricity to the heating plate automatically (the electricity is restored as the plate temperate goes down) so the machine does not go on fire.  These pads do not work.