Original Vietnam War Era United States Helicopter Flight Helmet Type APH-5 Size Medium

This is a Vietnam War era United States Helicopter Flight Helmet type APH-5 Helmet manufactured by Gentex Company in size Medium, Date 1967 !!!, The helmet is in overall very good complete condition with the liner, headset, boom mic, and clear visor. The helmet is maker marked by Gentex Engineering Company and is a size Medium. This is a rare Vietnam era original rare helicopter helmet in wonderful complete condition!Leather covered cushion pads on Styrofoam liner. Typical period equipment for US Army Aviation crews during Vietnam war. Rare matching set.
The US Army introduced their first flying helmet, the APH-5A or APH-5 Quartermaster helmet in 1959. It was an adapted version of the US Navy Aircrew Protective Helmet no. 5 (APH-5). The change was mainly in the communications system as the US Army used the same impedance standard as the US Air Force. With the introduction of the APH-5A the number of head injuries incurred during US Army aircraft accidents was reduced by half compared to the number of head injuries incurred before helmets were used.
The early examples of the APH-5A had the same thick foam rubber edge roll as the US Navy APH-5 and usually came in white color. Later examples had thin black rubber edge beading and usually came in olive drab color.