Recently acquired a second 3S mask. One by Auer, one by MSA. The Auer mask carries far less markings compared to the MSA, but Auer is mentioned on both masks. : r/gasmasks
MSA 3S Full Face Mask | MSA Safety Shop
Genuine MSA AUER brand Black MSA Full Face mask 3S Gas mask breathing apparatus | eBay
MSA Safety Works Advantage 3200 Full Face Mask Respirator Facepiece with Rubber Harness Medium 10028995 from MSA Safety Works - Acme Tools