








🖋️ Write sharp, write smart — the pen that means business.
The Uni-Ball Signo Knock Ballpoint Pen RT1 features an ultra-fine 0.38mm tip delivering precise, smooth writing with water-resistant, erasable ink. Its ambidextrous rubber grip and sleek snap closure combine comfort and style, making it a top choice for professionals and students seeking flawless, fast-drying performance.
| ASIN | B00B57W4QU |
| Additional Features | Erasable |
| Age Range (Description) | Teen |
| Age Range Description | Teen |
| Best Sellers Rank | #91,402 in Office Products ( See Top 100 in Office Products ) #2,371 in Gel Ink Pens #2,507 in Ballpoint Pens |
| Body Shape | Round |
| Brand | Uni |
| Brand Name | Uni |
| Closure Type | Snap |
| Color | Black |
| Customer Reviews | 4.4 out of 5 stars 812 Reviews |
| Drill Point | Extra Fine |
| Global Trade Identification Number | 04902778142653 |
| Grip Type | Rubber |
| Hand Orientation | Ambidextrous |
| Included Components | Ink Cartridge |
| Ink Base | Water |
| Ink Color | Black |
| Item Diameter | 15.4 Millimeters |
| Item Weight | 4.54 g |
| Line Size | 0.35 |
| Manufacturer | Uni |
| Material | Plastic |
| Material Type | Plastic |
| Model Name | Signo RT1 |
| Model Number | UMN15538.24 |
| Recommended Uses For Product | Writing |
| Style | 1 |
| UPC | 791836588878 |
| Unit Count | 1.0 Count |
| Water Resistance Level | Water Resistant |
| Writing Instrument Form | Roller Ball Pen |
A**A
New favorite pen ever
I used to write with the muji gel pen and decided to go for this une for its aesthetic and based on reviews, I am not disappointed. I usually never write reviews but this one is so worth the money. It writes fast the flow is amazing the 0.38 is perfect for my writing. Aesthetically it’s so elegant too the grip is perfect. Only drawback if I had to really be picky if that it smears a little if you don’t let it dry but it’s perfect for me as I’m right handed. Go for it!!
L**H
Best Pen
Uniball Signo 0.38 is my favorite pen regardless of color. Smooth flow, not scratchy like some ultra fine point pens, and no smudging for left handed writers!
Y**R
Best pen I have owned
Writes ultra fine. I love how the ink writes so smooth.
F**P
My new favorite pen
This pen is my new favorite. I use it as my primary pen for taking notes and recording information at my Security Services job. It's very comfortable in my medium sized hand, and has a very positive click when retracting or engaging. At .38mm it makes a very fine line and can write as small and legible at you want. The body is very sleek and is one of the more attractive pens I've seen. I gave it five stars because it's fantastic. That being said it is a .38mm. If you write very "vigorously" you may end up punching nice little holes in your paper. This pen is so smooth I don't even worry about it, but it can happen. I am in no way a pen expert, but I love how well this one lays down a nice thin line.
K**P
10 count does not mean you're getting 10 pens-misleading/false listing
The pen is gel, not ballpoint just so everyone knows, and 10 count pack of 1 gets you ONE PEN not TEN. I like the pen.
A**R
This is absolutely my new favorite pen. I'm a left-handed writer and always have ...
This is absolutely my new favorite pen. I'm a left-handed writer and always have to deal with that annoying smudge on the side of my hand every time I write across the line. This pen, with it's incredibly quick drying ink, fixes that. That, and the very fine, smooth-writing point, make it an easy choice for almost all my writing. I will note that the tip is incredibly fine, at 0.38mm, and there are instances where I'd prefer a bolder point. Still, 5 stars, no question. Buy this pen.
T**N
Good pen, ink is true RGB Green, very vibrant.
Pen tip is sharp so will tear fibrous/grainy paper if you put too much pressure in writing. Green is very vibrant and bright, think RGB Green. I'm looking for a hunter green ink pen but this will do for now. Good pen overall.
G**E
Great pen
This has always been one of my favored pens. Every time I lose it, I immediately by another. The ink is okay if you like gel, but I usually switch it out for a jetstream rollerball refill.
Trustpilot
4 days ago
2 days ago