The perfect pen for the field, Power Tank performs under the toughest conditions. Its pressurized ink cartridge allows for writing on wet surfaces, in extreme cold, & at odd angles, including upside down. The ergonomic textured grip ensures lasting comfort while uni Super-Ink™ technology protects against water, fading, & fraud.

Product Description

The uni-ball POWER TANK allows you to write on most surfaces, regardless of external conditions. Featuring the world’s first transparent pressurized refill tank, the POWER TANK utilizes internal compressed air pressure to consistently push out ink onto the paper.


  • Monitor ink supply with the world’s first transparent pressurized refill tank.
  • All-weather pen: Can be used in temperatures as low as -20°C and on wet paper.
  • Features innovative Super Ink™ that protects against water, fading, and fraud.
Point Sizes
1 mm
Ink Colors

All-Terrain Ballpoint

With its incredibly fast, free-flowing ink and a premium design, the all-terrain POWER TANK ballpoint pen delivers fluid, clean writing even on wet surfaces and in cold temperatures. This pen comes with a textured grip that provides comfort and control in the face of punishing weather. The POWER TANK also features exclusive uni Super Ink™, pigment-based ink that forms an indelible bond with paper to protect against water, fading, and fraud.

Transparent Pressurized Refills

Typical ballpoint pens rely on gravity to dispense ink, rendering them incapable of writing at upward angles. To tackle this problem, the uni-ball POWER TANK features a clever pressurized refill, allowing it to write in extreme conditions–on wet paper, horizontally, upside-down, and in temperatures as low as -20°C. The POWER TANK functions by compressing air inside of the cartridge, creating a uniform pressurized flow, making it the perfect tool in the field.