Product Details Name : Activated Carbon Dust-proof Face Mask Gender : Unisex Size : Free Size Material : Superfine fiber Applicable : Cycling /Running /Skiing /Training /Outdoor sports Function: Dustproof /Windproof /Anti-Smog /Anti-PM2.5 Features: Breathable /Flexible /Comfortable /Adjustable nose clip /Adjustable neck velcro /Personality /Colorful ​ Package:1PC Face Mask Notice 1.The ""pattern style"" and ""pure color style"" mask is made by diving material for it's durable and strong advantage.So it might smell a little bit,it's very normal,it will fade by itself,you also could put mask in 30℃ water for 15mins to remove it quickly:) 2.Our mask maybe a little small for European people who has large face 3.Only the ""pure color style"" is aluminium nose clip,other style is high quality plastic nose clip 4.Every mask is equip with one filter,if you want more,you could buy more filters together" 5.Usually one filter can be used for 30 days,It is recommended to change at any time during flu and heavy pollution periods