Uni-ball Uni Pin Fine Line Pen, 0.1mm, Precision Tip, Smooth Ink, Dark Grey

Tip size: 0.1mm. Ink color: dark grey. Flow: smooth and consistent. Tip durability: designed for long use. Pack: single pen. Practical uses include sketching, illustrations, and precision writing.

A 0.1mm tip creates extremely fine, precise lines with high detail. Thinner tips like 0.1mm produce sharper edges and are better for technical drawings, while thicker tips (e.g., 0.3–0.5mm) yield bolder lines and faster coverage.

Fine-line pens like this perform well on smooth, bleed-resistant papers such as marker paper, bristol board, and high-quality notebook paper. If your paper is very rough or highly absorbent, lines may appear lighter or feather slightly.

The ink is a professional, subtle dark grey that stands out clearly on light papers while remaining understated and legible on various backgrounds, making it suitable for technical drawings and professional notes.

Store cap closed when not in use. Use a light touch to avoid excessive pressure that could fray the tip. Test on scrap paper before finalizing a line, and keep the tip clean and dry for consistent ink flow.

Keep the cap on when not in use and store the pen horizontally or with the tip slightly upward to prevent ink leakage. Avoid extreme heat and keep the tip clean to maintain smooth ink flow.

Architectural and technical drawings, detailed sketches, precise lettering, and any work requiring crisp, fine lines with a professional dark-grey tone.

For fine, precise line work, this 0.1mm Uni Pin excels with ultra-fine detail and a durable tip. When comparing, you might also consider these on Fepy: Uni-ball Uni Pin Fine Line Pen 0.3mm (https://fepy.com/product/uni-ball-uni-pin-fine-line-pen-0-3mm) for bolder lines, Staedtler Pigment Liner 0.3mm (https://fepy.com/product/staedtler-pigment-liner-0-3mm) for archival-quality lines, Sakura Pigma Micron 0.1mm (https://fepy.com/product/sakura-pigma-micron-0-1mm) for widely-used archival ink, and Uni-ball Signo Gel Pen 0.5mm (https://fepy.com/product/uniball-signo-gel-pen-0-5mm) for smooth gel ink with a slightly different feel.

Anyone needing extreme precision for fine details, small-scale illustrations, hairline lettering, or technical diagrams will benefit from the 0.1mm tip, thanks to its ability to produce very delicate lines with a professional dark-grey appearance.

Yes. It is designed for everyday writing and drawing use. The ink is non-toxic and suitable for office, school, and personal projects. As with all writing instruments, avoid ingestion and keep away from small children who might swallow components.

The single-pack 0.1mm Uni Pin delivers ultra-fine precision for detailed work without committing to larger quantities. It’s an excellent choice when you need exact lines for technical tasks or meticulous illustrations, and it provides a reliable, long-lasting performance per pen. If you anticipate higher volume or prefer bolder lines, you might explore other tip sizes (e.g., 0.3mm) or additional pens from the same range for better overall value.