14 ms·
>Two breathing holes in the mask use small N95 filters that can be popped in and thrown out after each use. Still an N95. N95 melt-blown fiber remains the cri
by everybodyknows 6y ago
>Two breathing holes in the mask use small N95 filters that can be popped in and thrown out after each use.
Still an N95. N95 melt-blown fiber remains the critical, scarce material.