This pen is identical to those carried aboard Apollo flights 7, 8, 9, 10, and 11. It is a "space pen" and is able to be used in space at any orientation.
The Fisher AG-7 Space Pen was the result of a "million dollar research program" undertaken by the Fisher Pen Company during the 1960s, when NASA needed a pen capable of writing in the gravity-free environment of space.
On Earth, ball point pens rely on gravity for ink feed and have a small hole in the top of the ink cartridge through which the ink evaporates slowly. This pen is pressurized with nitrogen which forces the ink out through the tungsten-carbide ball, and the ink was specially formulated so it would not evaporate.
Transferred to the National Air and Space Museum from NASA in 1970.
Donated by the Fisher Pen Company