Originally invented for astronauts to use in space, the sealed and pressurized Fisher Space Pen can perform in temperatures from -30 degrees to 250 degrees Fahrenheit. This pen can also be used in zero gravity and at any angle-even upside down. It is the choice of search and rescue teams, law enforcement agencies, armed forces and anyone who demands reliability in a writing instrument. The Bullet Space Pen in the Cap Off style measures 5.3 in. when open and 3.8 in. when closed. The pen contains a medium point black ink cartridge and is available in a chrome or matte black barrel with a clip. Refill cartridges are sold individually.