Humidifier Pouch for SimplyGo Portable Oxygen Concentrator POC Power Supply The pillows come with dual wall For use in cushioning The pillows come with dual wall flaps that provide robust support and comfort The Hypo Filter adds a hypo allergenic layer to the standard S9 filter for improved filter performance ) the SimplyGo's Humidifier Pouch (shown here with a humidifier bottle sold separately) easily connects to the SimplyGo or the Mobile Cart for humidification wherever and whenever you need it The SimplyGo Humidifier Pouch attaches to the SimplyGo carrying case allowing you to have humidification added to your oxygen therapy when using in continuous flow mode