SOVIET HIGH ALTITUDE PRESSURE HELMET.
Metal, rubber, plastic, cloth and lambskin, with cloth tag. An original GS-h 6A high altitude pressure helmet, size N2M, product number 0641968, ca.1970. Complete with visor, padding, locking neck-ring with rubber gasket, integrated communications package (2 headphones and boom microphone) and oxygen hose.
These helmets were typically used on MiG-21, MiG-23, and MiG-25 fighter/interceptor airplanes, which flew at an altitude of 10,000 meters or higher.