What we have here is an anti gas mask that you see a lot on movies and games. This particular anti gas mask is seen in S.T.A.L.K.E.R.: Shadow of Chernobyl video game.
It’s a fan made kit created by KOT2020.
In S.T.A.L.K.E.R.: Shadow of Chernobyl, you are “the marked one” where you worked as an explorer or a guide to bring people into “the zone”.
The zone is a contaminated place full of radiation and has change flora and fauna into a weird steam-punk place. It’s safe to say that ‘the zone’ is a 2nd Chernobyl Power Plant after a massive gruesome explosion.
This is an easy mask model that can be made by anyone and suitable for cosplaying or Halloween.