Pack of 5 PM2.5 filters
•First layer made of spunbond cloth and filters micron-level dust
•Second layer filters industrial pollutants, automobile exhaust, second-hand smoke and pollen allergens
•Third layer made of activated carbon cloth which also filters micron-level dust
•Fourth layer offers filter density for smaller materials
•Fifth layer made of spunbond cloth
These are designed to be replaced every 1-2 weeks and cannot be cleaned.