The Fountain Pen Black Ink Cartridges Value Pack is designed to fit HERO 616 and 605 series fountain pens, providing a reliable and convenient refill option. Each cartridge is compatible with HERO fountain pens, ensuring a smooth writing experience with every use. The pack includes a generous supply of black ink cartridges, perfect for users who prefer a classic and professional writing style. Ideal for business professionals, students, and stationery enthusiasts, these cartridges offer a hassle-free solution for keeping your fountain pen inked and ready to go.