Uni-ball Uni Pin Fineliners, 0.3 mm, Ultra-Fine, Waterproof & Fadeproof, High Precision, Pigment Ink, Ideal for Technical Drawing & Writing - Black

Line width: 0.3 mm. Ink: archival pigment that is waterproof and lightfast. Tip: metal-clad for ruler work. Ink behavior: quick-setting to reduce smudges. Cap: snap-cap for reliable protection. Finish: black ink suitable for technical drawing and writing.

If you’re weighing options, consider: Sakura Pigma Micron 0.3 mm Black for a classic archival pigment line at https://fepy.com/product/sakura-pigma-micron-03-black, and Staedtler Pigment Liner 0.3 mm Black for a durable, widely used alternative at https://fepy.com/product/staedtler-pigment-liner-0-3-black. The Uni Pin offers a metal-clad tip for extra durability and a quick-setting ink for tidy lines, while the others provide their own tonal and handling characteristics.

Ideal for technical drawings, margins, labeling, architectural details, diagrams, and precise writing. It’s also suited for craft notes and any project requiring clean, crisp lines that scan well.

Keep the cap on when not in use. Use light to moderate pressure to maintain crisp 0.3 mm lines. Test on a scrap of your chosen paper to confirm line quality. Store capped and in a cool, dry place to preserve ink performance and tip integrity.

Yes. The pigment ink is designed to be waterproof and lightfast, helping your drawings and notes resist smudging and fading over time.

The metal-clad tip helps maintain a consistent 0.3 mm line as you draw. Prolonged heavy pressure or tip wear can affect line uniformity, so light to moderate pressure is recommended for long, uninterrupted lines.

It performs best on standard drawing and writing papers with smooth surfaces. It may bleed slightly on highly rough or very absorbent papers, so testing on a sample sheet is advised before committing to a large project.

Typically, Uni Pin fineliners are sold as disposable units with non-replaceable nibs and ink reservoirs. When the ink is exhausted or the tip wears, replacing the pen is usually the recommended option.

It offers archival, waterproof, and fade-resistant pigment ink with a durable metal tip at a competitive price point. If you value longevity and consistent 0.3 mm lines for technical work, it’s a strong choice, especially when you compare its performance to alternatives like the Sakura Pigma Micron or Staedtler Pigment Liner in their 0.3 mm variants.

Use a light touch to avoid feathering, draw with smooth strokes rather than multiple short passes, and allow ink to dry before touching the page. For scans, run a test page first to confirm no smudging and solid edge definition.

Yes. The pigment ink is designed for general use with low odor and non-toxic properties typical of archival inks. Keep the cap closed when not in use and store away from children as with other precision drawing tools.