Fisher Space Pen Ball Point Refill- Blue

Available in fine, medium, or bold point. This Blue Fisher Space Pen refill write underwater, upside down, at any angle, from -30 degrees F to + 250 degrees F, over grease, and in zero gravity! The "write out" for this cartridge is approximately 15,000 feet depending on writing style- this means you can draw a line approximately 15,000 feet long with the ink in one cartridge! This is as much as three times the "write out" of a standard ball point cartridge. For comparison, the typical "write out" of a roller ball (water based) cartridge is about half that of a standard ball point cartridge. Oil based ink has excellent shelf life- the cartridges will write after months, and even years, in the back of your desk. Fine is .9 mm, medium is 1.1 mm, and bold is 1.3 mm in size.