Soviet PMG Gas Mask

A Soviet PMG gas mask. These were in use from the early 1960s to after the fall of the USSR; it is most likely from the 80s or earlier due to discoloration of the rubber. The lens look good without obvious scratches and the strap, along with its buckle, are in great shape. None of the attachments, such as the filter and anti fog lens attachment, are available. I'm not sure of the size but the various markings on the rubber are "2," "33." and "810 C86."