M-S-A All-Service Gas Mask Model 'S' with All-Vision Facepiece

This is a vintage industrial gas mask kit manufactured by the Mine Safety Appliances Co. (MSA) of Pittsburgh, Pennsylvania, likely dating from the mid-20th century (circa 1940s-1950s). The set is housed in its original red-painted metal storage trunk, which features a detailed instructional paper label affixed to the inner lid. The mask itself, termed the 'All-Vision' facepiece, is constructed from molded black rubber with large circular glass eyepieces set in metallic frames, designed to provide a wide field of view. It includes a flexible corrugated black rubber breathing tube and an integrated speech diaphragm or exhale valve assembly at the chin. Accompanying the mask is a heavy-duty tan canvas harness with metal buckles, used to secure the canister and mask to the wearer. The instructional label is a critical component, listing technical specifications like 'Bureau of Mines Approval No. 1434,' illustrated fitting guides, a parts list, and maintenance procedures. Condition-wise, the mask appears largely intact, though the rubber shows some surface dust and potential hardening due to age. The red metal case exhibits significant paint loss and surface rust, particularly along the edges and lid. The instructional paper is yellowed with some minor staining and edge wear, but remains highly legible. The metal components show a natural patina and some oxidation consistent with industrial use and long-term storage.