These filters come in 10-pcs and can be used with most face masks. These are five-layer activated carbon, guaranteed to remove all particles within a few microns.

Application: Anti-dust, Smoke, Pollution, Ash

Dimensions: 4.75" x 3.25"

Filter function:

1.The first layer: high efficient filter cloth filter the dust of micron.

2.The second layer: meltblown cloth to filter industrial pollutants, automobile exhaust, second-hand smoke pollen allergies.

3.The third layer: high efficient filter cloth filter benzene and a smaller function of filtering dust microns.

4.The fourth layer: activated carbon cloth filter density, smaller material.

5.The fifth layer: spunbond cloth, filter out all kinds of harmful substances