How does one verify whether the product on Amazon is legitimate? Most masks have reviews referring to comingled fakes, and it's put me off buying.
If in doubt about fakes, don't buy it. I don't buy anything on Amazon that could result in absorption in the body. No food, no lotions, even certain fabrics can be radioactive in the case of "negative ion" mumbo-jumbo: This guy on youtube contacted the US Nuclear Regulatory Commission to force Amazon to delist these products with excessive negative-ion radiation: https://www.youtube.com/watch?v=3BA5bw1EV5I
A bit like Applied Science.