This Bio-Harness Assembly was worn under the Mercury pressure suit and was worn by John Glenn during his historic Friendship 7 flight on February 20, 1962.
The components consisted of an electrocardiograph signal conditioner, an impedance pneumograph signal conditioner and a DC-DC converter. These instruments monitored the physiological functions of the astronaut. The sensor attachment in the helmet was for respiration count.
Transferred from NASA - Manned Spacecraft Center