Mitsubishi Uni Smudge-Proof Mechanical Pencil Leads – 0.5 mm HB, Metal Case
This is two things in one: a genuinely excellent pencil lead, and a case worth keeping long after the leads run out. The uni Smudge-Proof leads use a nanodiamond-infused formula that bonds graphite particles quickly and firmly to the paper surface, resulting in a line that resists smudging by hand and — unusually — holds up cleanly even when highlighted over. The result on the page is dark, smooth, and consistent, with a break resistance that matches the quality of the formula.
The stainless steel case is a considered piece of design in its own right. It follows the iconic square silhouette of the original uni lead case, but replaces the plastic body entirely with metal, giving it a satisfying weight and a refined, minimal appearance. A circular thumb recess on the front activates a spring-assisted slide mechanism that opens and closes smoothly with a clean, positive action — more reliable and quicker to access than a pop-off cap. Each case holds approximately 40 leads and is fully refillable, so the case itself is designed to last a lifetime. When the leads run out, uni refill packs are available separately.
The case dimensions are compact enough to slip into a pencil case, pocket, or desk drawer without taking up any meaningful space.
Features
- Nanodiamond-infused graphite formula for smooth, dark, smudge-resistant lines
- Resists smudging by hand and under highlighters
- Break-resistant lead for consistent performance under firm pressure
- Full stainless steel case with spring-assisted thumb-slide mechanism
- Satisfying, positive open-and-close action — no loose pop-off cap
- Holds approximately 40 leads | Fully refillable
- Lead diameter: 0.5 mm | Grade: HB | Lead length: 60 mm
- Case dimensions: 68 × 20 × 7 mm
- Made in Japan
See all Mitsubishi - uni items
Original: $14.42
-65%$14.42
$5.05

Description
This is two things in one: a genuinely excellent pencil lead, and a case worth keeping long after the leads run out. The uni Smudge-Proof leads use a nanodiamond-infused formula that bonds graphite particles quickly and firmly to the paper surface, resulting in a line that resists smudging by hand and — unusually — holds up cleanly even when highlighted over. The result on the page is dark, smooth, and consistent, with a break resistance that matches the quality of the formula.
The stainless steel case is a considered piece of design in its own right. It follows the iconic square silhouette of the original uni lead case, but replaces the plastic body entirely with metal, giving it a satisfying weight and a refined, minimal appearance. A circular thumb recess on the front activates a spring-assisted slide mechanism that opens and closes smoothly with a clean, positive action — more reliable and quicker to access than a pop-off cap. Each case holds approximately 40 leads and is fully refillable, so the case itself is designed to last a lifetime. When the leads run out, uni refill packs are available separately.
The case dimensions are compact enough to slip into a pencil case, pocket, or desk drawer without taking up any meaningful space.
Features
- Nanodiamond-infused graphite formula for smooth, dark, smudge-resistant lines
- Resists smudging by hand and under highlighters
- Break-resistant lead for consistent performance under firm pressure
- Full stainless steel case with spring-assisted thumb-slide mechanism
- Satisfying, positive open-and-close action — no loose pop-off cap
- Holds approximately 40 leads | Fully refillable
- Lead diameter: 0.5 mm | Grade: HB | Lead length: 60 mm
- Case dimensions: 68 × 20 × 7 mm
- Made in Japan
See all Mitsubishi - uni items























