This is an original and completely intact early-WWI U.S. experimental M1917 "Brodie" helmet set. The helmet's exterior features original olive drab paint and wood chip texture. The helmet's interior brim is marked "OCco." This was one of a couple very early stampings only seen on experimental helmets produced by Crosby Manufacturing Co. When M1917 production accelerated, the Ordnance Department ordered Crosby to adopt a more uniform identification system, and were given the "A" prefix to mark future helmets. The chinstrap loops are secured by domed rivets - further denoting U.S. production. It retains its original size 7 oil cloth liner and leather chinstrap. The interior components have dried with time, but are still in exceptional condition for being more than one hundred years old.