![Permeable gear with the M3-IXA1-IVA1 Diaphragm gas mask. Permeable gear was used as early as WW1 and remained standard into the 1950s. My specific setup uses the second pattern “special” HBT uniform Permeable gear with the M3-IXA1-IVA1 Diaphragm gas mask. Permeable gear was used as early as WW1 and remained standard into the 1950s. My specific setup uses the second pattern “special” HBT uniform](https://preview.redd.it/8me49t6qyyx41.jpg?auto=webp&s=ce57fda07c4c8b0d65ea50c5eb2479cb66173b44)
Permeable gear with the M3-IXA1-IVA1 Diaphragm gas mask. Permeable gear was used as early as WW1 and remained standard into the 1950s. My specific setup uses the second pattern “special” HBT uniform
![AEF Gasmasks & Respirators 1917 to 1919 - (1917-1919) WORLD WAR ONE, RUSSIAN INTERVENTION - U.S. Militaria Forum AEF Gasmasks & Respirators 1917 to 1919 - (1917-1919) WORLD WAR ONE, RUSSIAN INTERVENTION - U.S. Militaria Forum](https://www.usmilitariaforum.com/forums/uploads/monthly_02_2015/post-5143-0-58084000-1425035492.jpg)
AEF Gasmasks & Respirators 1917 to 1919 - (1917-1919) WORLD WAR ONE, RUSSIAN INTERVENTION - U.S. Militaria Forum
![File:U.S. Marines in their gas masks during a gas mask drill, France, WWI (32916863386).jpg - Wikimedia Commons File:U.S. Marines in their gas masks during a gas mask drill, France, WWI (32916863386).jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/c/c1/U.S._Marines_in_their_gas_masks_during_a_gas_mask_drill%2C_France%2C_WWI_%2832916863386%29.jpg)
File:U.S. Marines in their gas masks during a gas mask drill, France, WWI (32916863386).jpg - Wikimedia Commons
![Original U.S. WWI M1917 SBR Gas Mask with Carry Bag, Instructions, and – International Military Antiques Original U.S. WWI M1917 SBR Gas Mask with Carry Bag, Instructions, and – International Military Antiques](https://www.ima-usa.com/cdn/shop/products/ONSV3608__08.jpg?v=1617307373)