This rare Gentek HGU-39/P dual visor/Ram horn flight helmet setup was used by the US Army, Marines, Air Force and Navy pilots of the OV-1 Mohawk aircraft circa 80s to the 90s and used either the MU-5 or MBU-12 Oxygen mask setup for high altitude flying.

It’s very similar to the SPH-3B by Gentek. Size is extra large.

Message me for more details, thanks