Duke University tested masks using lasers. The wanted to see how much came through various kinds of masks. Neck gaiters are so porous that, as the person exhales through it, the fabric breaks up the larger particles into smaller one which will hang around longer They say that if you can see light coming through your mask, or if you can easily blow through it, it's not doing its job.

Unfortunately, the purpose of a mask is to protect the public from the wearer, so if people insist on wearing gaiters or pulling their T-shirt up over their noses, the virus will continue to spread faster, as it has been doing lately.