Uni-ball Signo UMR-83 Gel Pen Refill 10-Pack

Ultra-Fine Precision, Ten at a Time.

Introducing the Uni-ball Signo UMR-83 Gel Pen Refill, the authentic Japan Mitsubishi replacement for the iconic uni-ball Signo retractable gel pen series. Engineered for maximum precision, the ultra-fine 0.38mm tip delivers sharper, finer lines than standard 0.5mm refills—perfect for small handwriting, dense study notes, and detailed annotations.

Compatible with standard Signo retractable bodies like the UMN-155-38 and UMN-103, this 10-pack ensures you never run dry. Choose from Black, Blue, Red, or sophisticated Blue-Black to keep your color-coded notes and professional documents looking their best.

✦ Key Features

• 0.38mm ultra-fine ball — delivers sharper, finer lines than standard 0.5mm
• Universal Signo compatibility — fits UMN-155-38, UMN-103, and more
• Smooth, water-resistant ink — consistent flow with no blobbing or skipping
• 10-pack value — ensures you always have a spare ready when you need it
• Authentic Japanese quality — guaranteed genuine Mitsubishi Pencil performance

✦ Specifications

• Tip Size: 0.38mm
• Ink Colors: Black, Blue-Black, Blue, Red
• Set Quantity: 10 refills
• Compatible Pens: Uni-ball Signo (Retractable series)
• Brand: Uni-ball (Mitsubishi Pencil)

Frequently Asked Questions

Q: Which pens do these refills fit?

A: The UMR-83 is the standard replacement refill for Mitsubishi Pencil's Signo retractable gel pen range in the 0.38mm diameter, perfectly fitting the UMN-155-38 (Signo RT1) and UMN-103 (Signo RT).

Q: What does Blue-Black ink look like?

A: Blue-Black offers a sophisticated alternative to standard ink colors. It writes with a distinctive, elegant blue undertone but remains dark enough to read clearly as black in photocopies and official scans.

Q: Does the ultra-fine tip feel scratchy?

A: No! Despite the ultra-fine 0.38mm ball, Uni-ball uses a premium gel ink formula that ensures a remarkably smooth, consistent flow from the first stroke to the last.