Not all face masks are the same. Be sure to do your research before deciding what face masks you will stock.
Given the use of face marks, the last thing you want is to discover that you sold something not fit for purpose, not safe.
I know of one business that recently purchased KN95 masks where the straps that held them in place were 2cm shorter than usual, making them unsafe for adults to wear.
I know of another business that bought surgical masks that were imported and found to be missing a protective layer.
Beware that there are some pitching face masks, taking money up front, and not delivering. This product niche is ripe for scammers.
This is a whole new product for retailers. if you do decide to play in this space, research is key.