Made in the USA and designed in conjunction with NASA and used on all manned space flights since the 1960's the Fisher Space Pen is still used to this day by NASA. The Fisher Space pen refill will fit into any Fisher Pen or any pen which takes a Parker refill with the help of the adapter which comes with each refill. The gas presurised writing system means that the Fisher refill writes continuously at any angle, in a wide range of extreme conditions on most surfaces.