This helmet is a Paratrooper variant of the M1 helmet. Paratrooper helmets used by the US military in the Second World War were equipped with modified liners with “A yokes” to attach a chin cup and snaps to to attach the helmet shells chinstrap to the liner, better securing it while parachuting. M1 helmets use a standard infantry style shell. M2 helmets use fixed “D bale” shells and snap-in chinstraps. M1-C helmets were used later in the war with “swivel bale” shells and with snap-in chinstraps. Paratroopers, and soldiers in general often times covered their helmets with nets to allow for attaching camouflage and reducing the amount of shine the helmet gives off. This type of helmet would be used from 1943 into the Korean War and possibly even early Vietnam.