The Sheaffer blue pen refill pack (5 cartridges, 96320) ensures a continuous supply of high-quality ink for your Sheaffer fountain pens. The pack includes 5 Sheaffer proprietary blue ink cartridges, formulated to flow smoothly without clogging the feeder or smudging the paper. The classic blue color offers excellent readability and a clean finish. It's the essential refill for users of Sheaffer fountain pens.