Designed for ease and convenience, these Platinum ink cartridge packs are the perfect match for Preppy fountain pens and all other Platinum cartridge-compatible models. Each box includes 10 individual packs, with 2 cartridges per pack, making it ideal for stocking up or sharing with customers. Whether for everyday writing or as a reliable refill option in retail settings, these cartridges deliver smooth, consistent ink flow in a compact, easy-to-store format. These not only fit the Preppy but all pens from Platinum!