The Holmes 103973 is the correct replacement for the following humidifier models:
The Holmes HWF100-UC2 Modular Wick Filter 2-Pack is a modular wick filter replacement for several different models of humidifiers. Arriving in a 2 pack, these wick filters are manufactured with CarbonX filter technology in order to aid your humidifier in improving indoor air quality. The filters also feature antimicrobial protection in order to trap microorganisms and small particles in the air.
These humidifier filters also include Arm & Hammer odor removal in order to provide air that is both clean and fresh. Be sure to replace your humidifier wick filters regularly in order to receive the best performance from your humidifier. Clogged and dirty filters reduce air quality and also reduce the life of your humidifier.
Holmes HWF100-UC2 Modular Wick Filter 2-Pack specifications: