The CDC reports that about 60% of KN95 masks sold in the US are fake. In fact, Colorado State University’s L’Orange—who has tested thousands of masks, including our picks—told us the most egregious fails have come from surgical-style masks as opposed to respirators. The CDC reports that about 60% of KN95 masks sold in the US are fake. A caveat: The “same” mask sold by the same company can differ depending on the retailer. As with our guide to cloth face masks, we’ll continue to add to this list of trusted respirator and surgical-style masks as new and better options become available.