Uni-ball ZENTO UBR-Z-05 Rollerball Pen Refill

The New Standard in Water-Based Rollerball.

Introducing the Uni-ball ZENTO UBR-Z-05 Refill, the authentic Japan Mitsubishi replacement for the all-new uni-ball ZENTO retractable rollerball pen. This refill uses a premium water-based ink formula that delivers an exceptionally smooth, fluid writing experience—combining the effortless flow of a liquid ink rollerball with the convenience of a click pen.

Equipped with a precise 0.5mm ball, it produces clean, consistent black lines that feel closer to a fountain pen than a standard gel pen. With its signature teal-green tip cap, the UBR-Z-05 is incredibly easy to distinguish in your stationery toolkit.

✦ Key Features

• 0.5mm precise ball — delivers a clean, consistent black line
• Water-based rollerball ink — exceptionally smooth and fluid writing feel
• Signature teal-green tip — easy to identify among other refills
• Uni-ball ZENTO compatibility — standard replacement for ZENTO retractable bodies
• Authentic Japanese quality — guaranteed genuine Mitsubishi Pencil performance

✦ Specifications

• Tip Size: 0.5mm
• Ink Type: Water-Based Rollerball
• Ink Color: Black
• Compatible Pens: Uni-ball ZENTO
• Brand: Uni-ball (Mitsubishi Pencil)

Frequently Asked Questions

Q: What is the difference between water-based rollerball ink and gel ink?

A: Water-based liquid ink flows much more freely than gel ink. This results in an exceptionally smooth, effortless writing experience with minimal hand fatigue, creating a fluid, expressive line similar to a fountain pen.

Q: Which pens does this refill fit?

A: The UBR-Z-05 is the standard replacement refill for the uni-ball ZENTO retractable rollerball pen range. It also features multi-purpose compatibility and fits many pen types that accept the standard UBR-Z format.

Q: What is the teal-green tip for?

A: The teal-green tip cap is the signature visual identifier of the ZENTO refill system, allowing you to easily distinguish it from standard Uni-ball Signo or Jetstream refills in your collection.