New Unknown Gas Mask!

Here we have what I think it is a kind of prototype/experimental/reduce production/ high voltage piece gas mask.

We dont have information about any model like this one. I have the theory that it is a japanese gas mask. Let's present the mask:

 
It actually looks like the british civilian model from WW2, but the big differents are:
-The filter is shaped as a japanese filter.
-It has two exhale valves in each side of the mask.
-And the rubber is quite more strong as the british mask.

Now we will check the filter:
As I said before, it really remember us the shape of japanese filters from WW2. The ''32'' is one of the very little marks it has.

 
The inside of this mask is quite interesting. It has a kind of diffuser of the entrance of air attached by snaps buttons.

 

And here we have a close shot of those snaps buttons, any information about them will be quite appreciated:

If we remove this kind of diffuser, we can see the filter, that really remember us the inside of the type 17 civilian gas mask:

I would consider this mask as a late war prototype of the civilian gas masks.