Mitsubishi Uni Jetstream 4&1 Multi-Function Pen 0.38mm + 0.5mm Mechanical Pencil

For those who like their writing tools to work quietly hard in the background, the Mitsubishi Uni Jetstream 4&1 Multi-Function Pen is a small triumph of engineering. Combining four ballpoint inks and a mechanical pencil into one sleek barrel, it’s designed to keep your desk—and your thoughts—efficiently organised.

At the heart of this pen is Uni’s renowned Jetstream ink, engineered to reduce writing resistance by up to 40% compared to conventional oil-based ballpoints. The result is a smooth, controlled glide across the page, whether you write quickly, lightly, or with purpose. Left-handers and fast note-takers will particularly appreciate the rapid drying time, which helps keep smudges firmly at bay.

The 0.38 mm extra-fine ballpoint tips deliver crisp, dark lines thanks to a high-density pigment blend—roughly twice the density of standard formulations—while the 0.5 mm mechanical pencil is ideal for diagrams, planning, or moments when ink simply won’t do. A spring-loaded tip and twin-ball mechanism support the low-viscosity ink while preventing leaks and backflow, ensuring dependable performance day after day.

What Makes It Work So Well

• Exceptionally Smooth Writing: Ultra-low-friction Jetstream ink reduces drag by up to 40%.

• Crisp, Bold Lines: High-density ink produces clear, dark writing on any paper.

• Clean, Reliable Design: Quick-drying ink and a twin-ball mechanism minimise smudging and prevent leaks.

Details

• Ink: Oil-Based (Black, Red, Blue, Green)
  
• Ballpoint Pen Tip: 0.38 mm
  
• Mechanical Pencil Tip: 0.5 mm
  
• Barrel Diameter: 13.7 mm
  
• Length: 147.6 mm
  
• Material: Oil-Based Ink
  
• Country of Origin: Japan