One layer: 50%
Two layers: 75%
Three layers: 90%
Plastic bag: 100%
Don't kill grandma. Make the right choice.
Follow
Yes, this is real.
They're finally admitting to the facts on masks, and why they just don't work well enough to matter.
https://rationalground.com/after-nine-months-we-still-know-masks-dont-work/
