Unknown PACT Respirator - Possible GM38 clone

I got this mask off of eBay on a bid and it was advertised as a NATO mask.
It turns out its most likely a PACT mask due to the filter and writing inside of the mask.
AZ or A2 is stamped on the forehead of the mask and inside is stamped 1982.
The mask appears to be a GM38 style mask covered in a canvas like material, any info on the mask would be appreciated.

Polish OM14 Respirator

Polish OM14 Respirator with a large EO14 filter.
The mask is very similar to the East German SCHM41 in terms of design and filter type. The differences being the OM14s filter is more of a water canteen shape and the metal on the inhale/exhale valve is a different material. The mask also appears to be actually white where most GP5 style masks are light grey.
The mask was used by Poland during the Cold war.

Czech CM4 Respirator

Czechoslovakian CM4 Respirator from the late cold war (Mask stamped 1984).
It uses a 40mm filter thread and has a decent voice diaphragm and exhale valve, it also has triangular lenses. It seems like it was introduced to replace the M10m or the Model Z respirator as it's a more modern design compared to the other two.
The mask visually looks like the West German M65 and also came in a bag with German writing on it.

Bulgarian PDE1

Bulgarian PDE1 Respirator. Another Warsaw Pact clone of the US M17 respirator. This one is probably the closest in design to the original M17.
Used by Bulgaria during the Cold War.

Soviet SCHMS Respirator

The SCHMS supposedly was designed by the East Germans to be a more effective mask that the military GP5 variant the M41, the lenses are designed so that a sniper or a soldier needing to use optics can raise them to the mask more easily. Adopted throughout the Warsaw Pact. The mask is also referred to as the "Deaths Head" mask due to it's skeletal appearance.

Soviet PMG respirator

The PMG was developed by the Soviets to utilize a lightweight combat effective mask, similar to the Nato masks. It has a skull faced design and was used by Valve in HL2 as the basis for the Metrocop mask.

Polish MP4 Respirator

Polish MP4 Respirator nicknamed the "Bulldog".
It's a basic clone of the US M17 mask similar to other Warsaw PACT clones such as the OM10, M10M and the PDE-1 respirators. The most interesting variant of the M17 clones was the PBF mask which took circular internal filters and was smaller than the other clones.

Czech Model Z/Polish MC1 Respirator

The Czech Model Z and Polish MC1 are identical masks. I'm unsure which I own but I think it may be the Polish model, it's quite similar to the French M51 in design.
It takes 40mm filters.

French M51 Respirator

French M51 Respirator by ANP, this is the Belgian export model.
The M51 was an early Cold War respirator that took 40mm filters and had a basic voice diaphragm built in the exhale valve.

Canadian C3 Respirator

The Canadian C3 Respirator was first issued in the early 60s, it is still one of the best gas mask designs available. The mask was based on the British Light-Anti-Gas Mark 3 respirator.
The mask was widely mass produced and sold, and was built under license by the Dutch.

Soviet GP4 Respirator

The Soviet GP4 respirator was issued to civilians from the 50s to the 70s. It was later replaced by the GP5 respirator which was to become the most mass produced respirator in World history.
The GP4 has appeared in much of the Artwork for the STALKER series.
The GP4 has a hose that can not be detached from the main body of the mask, it takes a 40mm filter at the bottom of the hose.

West German M65 Respirator

West German Drager M65 Respirator/Gas Mask.
The design was used by Israel to make the M15 gas mask.

Russian/Soviet PMK Respirator

The most modern Respirator in the Russian army, it replaced nearly all of the earlier PACT models and variants of it are still used today. This model is the first issued model and is dated 1989.
The mask is more similar to many of the modern NATO masks and features a voice box, a drinking tube, and a inner face piece.

Czech/East German M10M respirator

The M10 design was cloned from the American M17 and is visually very similar, many countries inside the Warsaw Pact adopted the design but the M10 was the only mask to be used by more than one Pact member.
Both East Germany and Czechoslovakia used two variants of this mask, the OM10 which was the basic mask with a voice diaphragm, and the M10 or M10M which also included a drinking tube.

Finnish M61 Respirators

One of the most common masks on the surplus market, the M61 came in 3 variants. The first being near identical to the American M9.All of the masks were manufactured by Nokia the mobile phone manufacturer.

The second having a slightly modified outlet valve, that could be removed or twisted.

The third featured a plastic voice box and outlet valve and was generally issued to higher ranking soldiers in the Finnish military, the mask was replaced in the late 90s by the M95 respirator.

British SR6 Respirator

The SR6 or S6 respirator replaced the Mark 2 & 3 Light-Anti-Gas Respirators in service with the British army. The S6 takes the Nato 40mm filter and has curved lenses to improve the peripheral vision of the wearer. The mask has a tap inside that can be adjusted to inflate the inside of the mask to create a tighter seal with the wearers face.
The SR6 was worn by the SAS during the Iranian Embassy hostage crisis labelled Operation Nimrod
The S6 was eventually replaced by the S10 during the 1980s.