Uni UMR-85 Gel Ink Pen Refill - 0.5 mm - Blue Black

Smooth ink flow. Color of ink is identical to the color of grip on the UMN-138 RT blue-black pen. This refill is usable in the UMN-138 pen as well.

These are great refills. Smooth, solid, and skip-free. They work in the Zebra dirfit jell pens too.