The Brodie helmet, called Helmet, steel, Mark I helmet in Britain and the M1917 Helmet in the U.S., was a steel combat helmet designed and patented in 1915 by the Briton John Leopold Brodie. Colloquially, it was also called the shrapnel helmet, Tommy helmet, or Tin Hat, and in the United States known as a doughboy helmet.
The Brodie helmet was standard issue among the US forces stationed in Hawaii and the US Marines. Many Marines hated the new M1 Helmet's they received, preferring the more familiar Brodie helmet, but quickly dropped their criticism after they realised that the old helmet couldn't protect as well as the M1.
The Helmet, steel, Mark I was the standard issued helmet for the British Empire, when the Race arrived in mid 1942. Many American veterans of the first world war remembered their old Brodie Helmets fondly, remarking how that they provided better protection from the rain when compared to their newer M1 Helmets.
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1=denotes a character who was a POV for one volume
2=denotes a character who was a POV for two volumes
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