Mask dont do anything to protect you. It literally says it in capital letters on side of the box Mask will NOT protect you from covid we breathe air not oxygen the oxygen in our air is 21% after a few hrs your oxygen rate falls to 17-19% This falls into critical range as u body is receiving to much carbon dioxide which in turns ur blood cells acidic. Acidic cells can turn cancerous. The mask is making u sicker and Mask don't work against covid it any virus.