On this day...

Super Chicken III

Jacques Blamont is born

First stratospheric balloon launch from Trappes, France

Attempt of launch of Star of Poland balloon

Third and last jump of Red Bull Stratos program

Project Loon starts providing connectivity in Puerto Rico on the wake of Hurricane Maria

First parachute jump from a hot air balloon by Garnerin

New stratospheric jump record set by Alan Estauce

On this day in 2014, Dr. Alan Eustace exCEO from Google used a state-of-the-art Pressure Suit Assembly to ascend to the top of the stratosphere beneath a large, helium-filled plastic balloon and sky dive back to Earth. He reached a maximum altitude of 135,889 feet before parachuting back to Earth, breaking the previous world record. He accomplished this mission by using a pressure suit alone for life support and foregoing the weight of a balloon gondola to ascend to the stratosphere.
In order to conserve the weight and expense of an oxygen supplies, the StratEx team decided to supply oxygen to Eustace only from the neck up. His oxygen mask was equipped with a valve that sent spent air, including carbon dioxide and humidity to the bottom part of the suit. In order for this arrangement to work, the suit had a rubber neck dam that formed a good seal. This plug was used when the suit was not being worn to maintain the integrity of the neck dam.
The Eustace-Kwan family donated this item along with the suit to the museum in 2015.