Upgrade your writing experience with the Mitsubishi Pencil uni JETSTREAM Ballpoint pen replacement core. This high-quality replacement core is designed to provide you with a smooth and effortless writing experience. Made in Japan, this fine nib pen is perfect for a range of writing needs, whether you are taking notes or drafting documents. The black ink and 0.38mm SXR-38 set ensure that your writing is clear and easy to read. This pen is compatible with a range of ink and lead colours, making it a versatile addition to your writing collection. The brand UNI is renowned for its quality and durability, making this pen a reliable choice for any writing needs.