The Fisher Space Pen (also known as the Zero Gravity Pen), marketed by Fisher Space Pen Co., is the original pen that uses pressurized ink cartridges and will write in zero gravity, upside down, underwater, over wet and greasy paper, at any angle, and in extreme temperature ranges.
These pens can write at altitudes up to 12,500 feet (3810 m). The ink is forced out by compressed air at a pressure of nearly 35 pounds per square inch (240 kPa). Operating temperatures range from -30 to 250 degrees Fahrenheit (-35 to 120 degrees Celsius). These pens have an estimated shelf life of 100 years.