German Leder B-Maske

The German Leder B-Maske was made of leather, and had two large oval plastic eyepieces.  They were mainly used for industrial purposes.  The first example features a UA filter connector, and was made by Dagerwerk Lubeck in 1935.  The second example uses a ZA filter connector, and was made by Drager in 1957.
Leder = "Leather"

Similar masks in my collection:  Austrian M-34, German ASM