Honeywell HCM-890B Humidifier: * Self-regulating evaporative system naturally adjusts output to the amount of moisture the air can hold at a particular temperature * Protec anti-microbial cleaning cartridge for fresher, cleaner moisture * Filter captures impurities in the water * 2 output settings * Perfect for small to medium rooms such as bedrooms and offices * Runs up to 12 hours per filling