ava@soon39c3:~:cursor_blinking::verifiedlesbian: (@star)

@sysadmin1138 Disregard if you are specifically not looking for alternatives not like the one you posted, but I can recommend Using 3M 6000-series-style half-face respirators. They take N95 and KN95 (FFP2/3 equiv.) filters on top of the regular filter cartridge and as such are suitable for protection against everything that a regular mask would also protect from. Bonus: Comfy over long periods, no foggy glasses, much easier to breathe in! 3M also sells an exhaust filter for these masks, if that is an exclusion criteria for you :)

Filter replacements of KN95-filters cost about 11ct (€) per piece, so 22ct for the two ones needed in a mask, naturally