The Pilot RFJS-GP-M Black Medium Refill is a genuine Pilot ballpoint pen refill designed for compatible Pilot retractable ballpoint pens. Filled with rich black oil-based ink, it delivers smooth, consistent writing with clean, reliable lines through its medium point. Ideal for document writing, note-taking, signatures, journaling, and everyday office or school use, this genuine Pilot refill restores your pen's original writing performance while extending its lifespan.