The ResMed HumidX is a disposable waterless humidifier for AirMini™ CPAP machine designed for dry environments. Must be replaced within 30 days of opening (1, 3 or 6 pack). HumidX is a waterless humidifier that’s designed to provide you with more comfort by retaining the moisture and heat in the air you breathe, and offering relief from possible dryness and congestion. When you exhale, heat and moisture is captured and stored within the HME’s tiny paper ridges. When you inhale, this heat and moisture is released to humidify the air you breathe in. HumidX can be inserted directly between the mask connector and the vent, providing effective waterless humidification at a compact, effective and comfortable level. It is suitable for normal/average conditions of medium to high humidity, and medium to high temperatures.