3M 9501V mask used in PM2.5 dust environment or used to prevent respiratory disease infection. 3D design hugs the face prevents dust and does not cause fog when wearing glasses; has 3M's exclusive 3M Cool flow breathing valve with 1-way airflow mechanism; There is an aluminum clip to help hug the bridge of the nose comfortably. 4-layer structure including PP non-woven fabric, antibacterial fabric, and electrostatic filter cotton.