Superb and very rare USM1 Airborne helmet of the 517th Parachute Infantry Regiment. The helmet was field modified, performed by « Riggers ». What makes this helmet modification stand out is how the helmet's chin straps were altered in combination with a distinctive pattern left on the helmet body as a result of having camouflage paint applied to it over a shrimp type netting material. Period photographs illustrate various results of airborne modifications performed by units in the field but in the case of the 517th AB modification, the « Riggers » achieved this by first cutting both helmet straps off to equal lengths and sewing adjustment buckles scavenged from field gear to their ends. A scratch made fabric chin cup was then fed through the buckles allowing the helmet to be adjusted until securely tightened to the wearer’s head. Period photographs also illustrate that most of the 517th’s uniforms and gear had camouflage patterns added to them by spraying them with paint. The unit’s helmets were covered with a locally acquired shrimp type netting material over which this camouflage was applied resulting in a unique pattern distinctive to the 517th PIR. The exterior of the helmet is in overall excellent condition, still retaining well over 95% of the green and black camouflage. Some camouflage paint is also present ton one of the adjustment buckle. The original specific web chin-up is present. The original liner comes with the helmet, made by « Firestone ». The interior is almost complete and remains in as-found condition. The leather chinstrap is present but the back neck strap is missing. The leather sweatband shows actual use and is damaged. This is one of the rarest US Airborne helmet, it is a unique opportunity to acquire one of them !