Enhance your writing experience with these high-quality fountain pen ink cartridges, designed for smooth and consistent ink flow. Each cartridge measures 50mm in length with an outer diameter of 5mm and a bore diameter of 3.4mm, making them compatible with most standard fountain pens. These easy-to-use ink cartridges allow for a quick and mess-free refill, ensuring your hands stay clean during ink replacement. Perfectly suited for office, school, and home use, these cartridges provide reliable performance for everyday writing needs. Key Features: · Standard Size Compatibility: Ink cartridge length of 50mm, outer diameter of 5mm, and bore diameter of 3.4mm fit most fountain pens—please verify your pen size for compatibility. · Easy and Clean Ink Replacement: Designed for hassle-free ink changes without messy spills or dirty hands. · Smooth and Consistent Ink Flow: Delivers an even output for a pleasant and uninterrupted writing experience. · Versatile Usage: Ideal for use in offices, schools, and home environments to meet daily writing demands. · Multiple Ink Colors Available: Choose from dark blue, black, or red ink to suit your writing style and preferences. · Bulk Quantity Options: Available in packs of 50 or 100 cartridges to ensure you have an ample supply on hand. Specifications: · Ink Colors: Dark Blue, Black, Red (optional) · Quantity: 50pcs or 100pcs (optional) · Ink Cartridge Length: 50mm · Ink Capacity per Cartridge: 0.9ml · Cartridge Outer Diameter: 5mm · Cartridge Bore Diameter: 3.4mm Package Includes: · 50 x Fountain Pen Ink Cartridges These fountain pen ink cartridges combine convenience, compatibility, and reliability to enhance your writing experience, making them an essential accessory for students, professionals, and fountain pen enthusiasts alike.