TWSBI Precision Fountain Pen - Gemini Blue

The second finish in TWSBI's Precision line, a metal-bodied piston filler drawn from the drafting tools of architecture and engineering studios. The body, cap, and grip are blue anodized aluminum, cut into a six-sided profile with polished bevels between the facets — so the pen reads as two-tone, a steely blue against bright silver edges that shift as the light moves. Chrome-plated clip, finial, and rings finish it. Named for the constellation, and a limited edition alongside the standing gunmetal version.

What makes it special

• Two-tone effect built into the shape: blue anodized faces with polished silver bevels between them, rather than applied decoration
• Machined aluminum body and grip — heavier and more solid than the resin ECO or the acrylic 580 at 30 g
• Hexagonal barrel with an angled clip, a departure from TWSBI's rounded demonstrator shapes
• Ink window in the grip section instead of a clear barrel, for a more discreet look on a desk
• Piston filler holding about 1.0 ml, filled straight from the bottle with no cartridge or converter
• Two o-rings on the piston knob so the cap posts securely rather than sitting loose
  
• Fully user-serviceable; ships with a wrench and silicone grease for disassembly and maintenance

Specs

• Type: Fountain pen, broad nib
• Nib: German-made stainless steel
• Body, cap & grip: Blue anodized aluminum with polished bevels
• Filling: Piston (bottled ink only — no cartridges or converter)
• Ink capacity: ~1.0 ml
• Cap: Screw closure, postable (o-ring secured)
• Capped length: 137 mm (5.4 in)
• Uncapped length: 125 mm (4.9 in)
• Posted length: 167 mm (6.6 in)
• Weight: 30 g total (20 g barrel, 10 g cap)