Were you flying to Europe? I think they banned cloth masks and said medical masks only. As I figured you were flying in the US, I would think US rules would apply so real ones would have FDA approval although I think the US is still pretty lax and allows cloth masks/gaiters although I'm not sure about airlines. I think they go up to FFP3. You can even get KN95's with FDA approval, the headband ones are better than earloop. There are probably some coupon codes floating around on slickdeals.net. 2021 takes 7% off.
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Probably because they didn't go for FDA approval or some such certification although it's possible they were, they just didn't get any certifications. I did buy some masks in the US once that had ASTM level 2, but then later on, they got approved for ASTM level 3 so they just changed the labeling and discounted their old batch that had the old labels.