Fisher Space Pen

The iconic Fisher Space Pen was developed in 1967, when Paul Fisher realized that there was no existing pen which could perform reliably in the vacuum of space. After 18 months of rigorous testing, it was ready.

The sealed pressurized ink cartridge writes in almost any condition; -34 degrees C to 121 degrees C, underwater, on x-rays, and at any angle, even upside down! There's a reason it's been hailed as the most advanced writing instrument in the world!