?Five Layer Protection?: 1st layer of spunbond cloth filters micron-level dust. 2nd layer filters industrial pollutants, automobile exhaust, passive smoking, and pollen allergens. 3rd layer of active carbon cloth filters micron-level dust. 4th layer offers. ?Mask filte material?: Dust mask replacement filter material: Non-woven, Active Charcoal cloth. ?Protect ourselves?Best for protecting your mouth and face from Dust, Haze, Allergies, Smoke, Pollution, Ash, Pollen, Gardening, Crafts, etc. ?Suit for?:Suit for all mouth mask insided with fliter slot.Compatible with majority of Dust Masks available in the market. 30 x Filters.