asks how trebor is selling masks in the USA without FDA approval...

first, i have seen no evidence that trebor is actually selling their masks in the USA. but if they are, the answer is easy. all they have to do is make it clear that the FDA has not approved the masks and make sure that they make no claims the FDA objects to.

vitamin companies do it all the time. they just put the standard spiel on the label that they make no claims about the effectiveness of the vitamin, and that it hasn't been approved by the FDA. then they are free to sell as much as they want. and they do. and US citizens are used to the spiel and simply ignore it for the most part. almost nobody bothers to read the disclaimers that the FDA demands.