The Italian Maschera Antigas S.A.B. M.33 was very similar to the Belgian M1934, but the facepiece was made with smooth rubber and lacked an exhale valve.  This example was used with a rebreather called the Autoprotettore S.C.M. 37, and was made by Società Anonima Bergomi around 1933.

Maschera Antigas = "Gas Mask"

Autoprotettore = "Self-Protected"

S.C.M. = Servizio Chimico Militare = "Military Chemical Service"

Società Anonima Bergomi = "Bergomi Anonymous Society"