The Schneider SN6602 red pen refill pack (6 cartridges) ensures a constant supply of vibrant red ink for fountain pens and cartridge rollerball pens. The pack includes 6 short, standard international format cartridges filled with highly saturated, quick-drying liquid ink that won't smudge on paper. The vibrant red color is perfect for teacher corrections, highlighting, and artistic writing. An essential item for students, educators, and office professionals.