@phile That's what I thought it might be...from the get go of this Pandemic though, those have not been the safest thing to be using to avoid spread or contraction, especially now with the Omicron....just saying. Better to use the Kn95 or N95s designed for virus barricade. The other problem is the majority of those sold online could be fakes made in China, so need to look closely at the product for stamps of model and institute numbers, etc. We should read up on the true model numbers to look for...probably on CDC website, or if you aren't from the US, your country's health authority. May Omicron be the final variant...wishful thinking!