US M1917 steel helmet, also known as the Brodie pattern, as used by the American Expeditionary Forces during World War I. The helmet is constructed from a single piece of steel with a raw, unrimmed edge. Stamped into the underside of the brim is the mark FS 18, which identifies the steel batch as being produced by the Firth-Sterling Steel Co. The exterior is finished in textured olive drab paint and features a hand-painted unit insignia on the side for the 27th Infantry Division. This insignia depicts a red circle containing an intertwined NY monogram surrounded by seven stars representing the constellation Orion. The interior retains a partial black oilcloth liner and a felt crown pad with a central rubber bumper. It includes a two-piece leather chin strap with a sliding metal buckle.