We just got a nice lot of these Czech military M10 gas masks. 1970's and 890's manufactured and just released from Czech reserve stocks. These masks were a copy of the long-serving US M17 design.
These masks are unused, and come with the filters still sealed in the original packaging. Unlike the filters found in a lot of the imported gas masks these filter has NO ASBESTOS. Use care when buying other masks as many Soviet era masks had asbestos in the filters.
Due to the age we wouldn't recommend these masks for something like nerve gas (are you going to be in some anyway?) but we have played around and tested them to work to protect from CS / tear gas and pepper spray.
These do come sized- we have size 1 that is a small/medium and size 2 that is a medium/large