Mask Nerd Short - What is a KN95/KF94/N95

What are the differences between KF94, KN95 and N95 standards? Cover it here, also excuse my mistake in the first 10 seconds, I meant to say respirator, but for some reason said respiratory. Didn't notice until now....so it stays.
Fit,Fit,Fit Video: • Mask Nerd Short - Fit,...