6 PACK Lot of Blue Fine Point Fisher Space Pen UNIVERSAL Refills

Lot of six (6) brand new sealed packs of authentic Fisher Space Pen Fine Point Universal #SU1F BLUE refills.Paul Fisher developed the pressurized refill for NASA in 1965. They are still in use today on manned space flights because it performs when other pens fail. The combination of tungsten carbide ball point and thixotropic ink in a hermetically sealed cartridge pressurized at nearly 35 pounds per square inch allows it to write in freezing cold, boiling heat, underwater and at any angle, even upside down!