5-Layered Filter Design : - These kn95 face masks are made of two layers of non-woven cloth, two layers of melt-blown fabric, and one layer of hot air cotton. - From outside to inside, the second and third layers are melt-blown cloth. - When they are produced, they are easy to stick together, which will cause you to mistake them for one layer, You can separate them by rubbing them. **For further product information, please contact Chat Support**