Fisher Space Pen Black Ink Refill Fine Point SU4F - Pressurized for Upside Down, Underwater, and Extreme Temperatures

The Fisher Space Pen Black Ink Refill, Fine Point (SU4F) is a pressurized refill built for anyone who writes in demanding conditions. Designed for professionals and adventurers alike, it ensures reliable ink delivery when it matters most.

• Ink color: Black ink with a fine point for precise, legible lines.
• Compatibility: Fits most 2- and 3-color ballpoint pens, making it easy to upgrade existing pens.
• Pressurized ink: Maintains consistent flow in extreme temperatures and at odd angles; writes upside down, underwater, through grease, and in harsh environments.
• Diameter: 0.92" diameter, designed for a secure fit in compatible pen bodies.
• Packaging: Hang packaged for simple display and quick replacement in stores or at your desk.

Whether you’re on a field service call, exploring outdoors, or tackling tough maintenance at a workbench, this refill keeps you writing when other inks fail. The pressurized cartridge ensures ink reaches the page in cold or hot temperatures, even if your hands are dirty or greasy. The fine point provides clean, precise lines for notes, measurements, or quick sketches, helping you stay organized and accurate. By fitting a wide range of two- and three-color pens, it also offers practical flexibility, allowing you to refresh multiple devices with a single, reliable refill and minimize downtime.