uni pin Fine Line pens are waterproof fineliner pens designed for drawing, sketching, technical work, and handwriting. They use fade-resistant pigment ink and come in a range of nib sizes, from very fine detail tips to broader line widths.
One of the main selling points is that the ink is waterproof once dry, making the pens useful for mixed media work, especially when adding watercolour over ink drawings.
What I Use Them For
I mostly use uni pin pens for:
- Handwriting and notes
- Sketchbook line work
- Journalling
- Outlining pencil drawings
- Simple illustrations
The pens feel controlled and consistent, which makes them easy to use for longer writing sessions as well as sketching.
Watch Video – Writing with the 0.03 uni pink Fine Line Pen
uni pin Pen Sizes
The nib size just depends on what you intend to use them for and what you’re comfortable with. They come in the following sizes:
- Ultra-Fine: 0.03 mm, 0.05 mm
- Fine & Medium: 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm
- Bold: 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.2 mm
Are uni pin Pens Waterproof?
Yes – the ink is waterproof once fully dry.
That’s one of the biggest reasons artists use them for sketching and ink drawing. You can add watercolour or light washes over the lines without major smudging.
Final Thoughts
I think uni pin Fine Line pens are a good choice if you want dependable waterproof fineliners for sketching, drawing, handwriting, or journalling.
They’re not luxury pens, but they’re consistent, practical, and reasonably affordable. For everyday creative work, that’s usually enough.
Where to Buy uni pin Fine Line Pens
You can usually find individual pens or multipacks in art supply stores. I buy mine online from Jackson’s Art Supplies – see links below. (If you go ahead with the purchase, I may earn a small commission at no cost to you).