World War 1 French Model 1915 'Casque Adrian' Infantry Helmet. The M15 Adrian helmet (Casque Adrian) was a combat helmet issued to the French Army during World War I. Introduced in 1915, it was the first modern steel helmet and it served as the basic helmet of many armies. The helmet retains most of its original dark blue/grey paint, along with the original French "Flaming Bomb" badge with the standard 'RF' (Republique Francaise) initials on the bomb. The helmet is complete with its original leather liner, the chinstrap is unfortunately missing. Nice original helmet!