THIS IS ONLY FOR A 3 PACK OF A CHANGEABLE FILTER FOR THE VB MASKS.
The filter includes 5 layers, non-woven fabric+non-woven fabric+meltblown+non-woven fabric+non-woven fabric. Its filtration rate of PM2.5 is greater than 95%. It is recommended to replace the filter every two weeks.
DISCLAIMER: Face mask has neither FDA registration/approval nor application for 510K thus not aimed to be used as medical supply to hospitals.