This M3 flak helmet was the first helmet designed expressly for use by American bomber crews. The interior is marked "331" - most likely indicating use by the 331st Bombardment Group (Heavy), which saw combat in the Pacific Theater of Operations. The M3 flak helmet has large felt-lined, hinged ear covers on its sides to accommodate a communications headset. Unlike M1 helmets, the M3 features a built-in suspension system, which is in excellent condition, retaining its original headband. The headband is also unlike the M1 helmet's standard headband in that it was never issued with leather padding. The original, and often-missing, felt ear pads and web chinstrap remain intact on this example. The exterior had a flocking coating to prevent the airman's skin from sticking to the metal at high altitudes and freezing temperatures. The helmet's original factory paint shows consistent wear throughout, but retains much of its flocking texture. From 1942 to 1944 only 210,000 of these helmets were produced by the McCord Radiator & Manufacturing Company; compared to 22 million standard M1 helmets, making this an exceptionally rare piece - especially in this condition.