Replacement filters for Ellessco MyAir comfort mask. Filters adhere to the inside of the MyAir fabric sheath, and block 99.997% of airborne particles and contaminants down to 0.1 microns. MyAir filters also retain 88% of the moisture from your exhaled breath, supporting hydration and comfort of respiratory tissues. Helps keep you hydrated while blocking out the things you dont want to be breathing. Data from independent microbiology & permeation test lab results for MyAir filters.