1,200 Pcs PM2.5 Activated Carbon 5 Layer Face Mask Replacement Filters 30/Box

Dimensions: 4.75" x 3.25" These filters come in 30-pcs per box with a total of 40 boxes in a case. They 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