WWI British Army Hypo Helmet gas mask was the earliest pieces of protective masks issued to British and Commonwealth soldiers to defend against new deadly gases like chlorine and phosgene. The helmet is constructed from chemically treated fabric designed to neutralize harmful gases, with a rectangular viewing window made of mica. The mica panel has a few cracks, with two small flakes detached from the main panel but still present with the mask. On the reverse is an “O.H.M.S.” (On His Majesty’s Service) tag, suggesting its cataloging as part of British WWII wartime documentation, likely for a museum display.
Condition: II