The M9 Gas Mask was adopted in 1947, based on improvements to the facepiece design of the M5 Assault Gas Mask. The M9 gas mask facepiece was made of an improved synthetic molded rubber composition that remained flexible in cold temperatures. The M9 was made in three sizes (S, M, L). It was also made in two styles, one with the canister on the right of the facepiece and one on the left.
Changes to the rectangular carrier bag resulted a change of nomenclature in 1951. Although only the bag changed, the mask model number was advanced to become the Mask, Protective, Field M9A1. Over 3 million of the masks were procured until it was declared obsolete in 1959. Early production masks were black, but most M9 and M9A1 gas masks were grey or olive in color. The 60mm activated charcoal canister was the M11, painted dark gray or black.
M9 Gas Mask Packaging
Gas mask, M9 along with Carrier, M11 and accessories were supplied in a sealed can.
Innovative packaging was used to distribute and supply the Mask, Gas M9 and the Mask, Protective, Field M9A1. All components (M9 or M9A1 Gas Mask, Carrier, Canister and accessories) were hermetically sealed in a metal can as shown in the photo above. A second, inner can held the canister. A coffee can type key was attached to the top of each can for opening it.
The two cans were olive drab in color. The outer can was marked in yellow with an indication of the gas mask size (S, M, or L) and the position of the canister (R or L). The inner can was marked in black with canister information.
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