Transcend Micro PureFresh Filters

The PureFresh filters keep the air your Transcend Micro pulls in clean, trapping dust, pollen, and airborne particles before they reach you. The foam is reusable: rinse it weekly and replace it about every 6 months.

These are the Micro's air filters, not humidification. Waterless humidification for the Micro is the separate Transcend AirMist HME.