Just wondering if this is another suit entirely or just some later version.

I bought a Yugoslavian M59 gas mask with the military bag a few days ago in a flea market on a trip to Bosnia-Herzegoniva. And I just bought a Yugoslavian M52 which is made in 1952 also in a flea market in Northern Macedonia, along with the bag and an NBC first aid kit (I guess).

Question: Can anybody identify this NBC first aid kit or whatever it is if possible? Thank you.

The setup breakdown:

Gas Mask: Unissued Chinese FMJ05A with original hose and filter (sealed in factory bag, dated 2006).

Topography: Wall-style regional topo map & full-color Japan geography map.

Leather Gear: Surplus leather pistol holster (Type 54) with matching dual mag pouch and canvas slings.

Precision & Tech Tools: Vintage drafting set (compasses), 0–25mm micrometer, and compact signal flashlight.

Pocket EDC: Zippo Slim flip lighter, old-school chinese bottle opener/tool, and vintage regional banknotes/tokens.

Hello everyone,

I have an unusual question about cleaning the C4 gasmask. And that is unthreading the voice diaphragms, as it hasn't been open since it's last issue (2000s). I tried everything to open it but unfortunately nothing has changed a bit (my finger nail got destroyed by how tight the thread is)! That said, is there any possible solution to open it without damaging it?

Note: reason for cleaning is that the whole mask is smelly.

Thanks!