The S.B.A. L.702 was the most abundantly produced Belgian gas mask before and during World War II. They were made out of high quality rubber with non-replaceable glass eyepieces. These were for civilian use. The top two examples are equipped with a 25mm filter, while the bottom example was fitted with a 40mm filter for export to Sweden and designated "Typ 14". All were made by Société Belge de l'Azote between 1938 and 1940.
Société Belge de l'Azote = "Belgian Society of Nitrogen"
Similar masks in my collection: N/A
"Ste BELGE DE L'AZOTE ET DES PRODUITS CHIMIQUES DU MARLY"
"COUVRE-FACE Brevete L 702 Type agree par le gouvernement No 158"