The GM-38 was used by the German Army in World War II and was created as an upgrade for the GM-30. It was produced by the manufacturing companies; Drager and Auer.
The mask's face piece was made entirely from rubber, which supposedly protected against newly discovered chemicals. This mask has a variety of colours, which represent why they were used. Masks with tan painted parts were used in the tropics of Africa in World War II as it is painted in 'sand colours'. The mask has a 5-pointed strap harness which is tightened with two straps in the mid-section and another two near the bottom. The mask was issued in a canister which was carried around the neck but the mask also has its own carrying strap with which it could be carried.
After world war 2, some gas masks were in limited use with Austria. And a special variant of this mask was used by pilots. It had a hose on the left/right (depending on the aircraft it was used in).
The filter thread is 40mm and the filter is quite heavy and the frontal weight pulls the mask forward.