Fisher Space Pen Black Medium Ink Refill SPR4 - Pressurized For Upside Down Underwater Writing

The Fisher Space Pen Black Medium Ink Refill SPR4 is a pressurized refill built for professionals who demand reliability in extreme conditions. Designed to fit Fisher Space Pen models that use the SPR4 cartridge, it delivers dependable black ink when and where you need it most.

• Ink Color: Black ink for clear, legible writing across papers and surfaces.
• Point Size: Medium point provides balanced, easy-to-read lines suitable for daily notes and technical diagrams.
• Refill Model: SPR4 refill compatible with Fisher Space Pen systems, ensuring a precise fit and smooth performance.
• Write-Anywhere Capability: Pressurized ink maintains consistent writing upside down, underwater, through grease, or in extreme temperatures.
• Packaging: Hang-packaged for straightforward retail display and quick replenishment in stores or on the go.

This refill is ideal for field technicians, engineers, researchers, and travelers who need dependable ink in challenging environments. Expect steady ink flow with minimal skipping, even when conditions are less than ideal, so your notes, measurements, and labels stay legible. The SPR4 is a practical upgrade for anyone who relies on a Fisher Space Pen for mission-critical writing.