The Zeltbahn 31 was developed in 1931 and found its origin in the square Reichswehr tent.
It is made of a water repellent material called Makostoff
completely field grey example.
These are mostly early war shelter quarter given to other organisations then the military.
Basically the shelter quarter was used for 2 purposes: to make a tent and as a rain poncho,
but the shelter quarter could be used for a variety of purposes.