These ink are suitable for calligraphy and other detailed writing tasks. The ink ensures that your writing is smooth and precise, making it suitable for both everyday use and special projects. The are easy to install, allowing students to quickly switch between different colors or ink as needed. Features -Color:Assorted Color -Material:Plastic -Size: 5.00X0.70X0.70cm/1.97X0.28X0.28in -Note: 3.4mm caliber ink -suitable compatibility: fits fountain pens, ensuring a secure and reliable fit -Simple replacement: the ink are designed for easy replacement, making them easy to use -Smooth and reliable: the ink flows smoothly, preventing clogs and leaks, ensuring a pleasant writing experience -Versatile usage: ideal for use in educational, professional, and personal settings, catering to diverse needs -Suitable for everyone: great for both new and experienced writers, providing a writing experience Package list: 10 Fountain Pen Ink (100pcs)