Uni | Zento Ink Refills

The uni-ball ZENTO UBR-Z refills are genuine replacement refills made for the uni-ball ZENTO pen range (including ZENTO Flow). They use ZENTO water-based pigment ink, engineered for a soft, low-friction “cushioned” writing feel while keeping lines clean and controlled. The ink formulation is designed to reduce drag compared with conventional water-based ballpoint inks and to help limit feathering, bleed-through, and show-through, making these refills a strong choice for everyday notes, work writing, and journaling.

Because they’re refills, you keep your favorite ZENTO body and simply swap the cartridge to restore that smooth ZENTO writing performance.

UBR-Z-38 (0.38 mm) — Black

A fine, precise option for small handwriting, planners, margins, and detailed notes. The 0.38 mm tip is ideal when you want tight, tidy lines and controlled character shapes without sacrificing smoothness.

UBR-Z-05 (0.5 mm) — Black

A versatile everyday point size with a slightly bolder line than 0.38 mm. The 0.5 mm tip is great for fast note-taking and general writing where you want clear readability with a smooth, consistent flow.