Quarantine Coloring Book
The Belgian M1934 was nearly identical to the M1931, but the eyepieces were 60mm instead of 50mm. It was used by the Belgian military until 1951. This example was made by Bergougnan Belge in 1938.
Similar masks in my collection: Belgian M1931, Belgian AG15, Belgian AG20, Italian S.A.B. M33, Italian I.A.C. M31, Spanish M33