RUIERXIN from 2020 - PRC 
 
4 layers:
First -  SS spunbond 60 g/m2
The second is antibacterial material 99-meltblown 25 g/m2
Third - antibacterial material 99-meltblown 25 mg/m2
4th - SS spunbond 60 g/m2
 
Each mask has its own individual packaging with a slider lock.