TWSBI Eco Fountain Pen in Cosmo with Onyx

The TWSBI Eco Fountain Pen in Cosmo with Onyx captures the mystery and beauty of a starry night sky. Its shimmering Cosmo resin glows with subtle hints of deep blues, purples, and silvery flecks, creating a cosmic effect that’s different with every pen. The translucent acrylic barrel lets your ink color shine through, while the onyx black trim adds a bold, modern contrast. This pen is as much a statement piece as it is a reliable writing instrument.

Crafted from high-quality resin and acrylic, the Cosmo finish is the result of a careful casting process, giving each pen unique variations in color and pattern. No two pens are exactly alike, making your Eco truly one-of-a-kind. The stainless steel nib glides smoothly across the page, while the piston-filling system ensures consistent ink flow for an effortless writing experience.

The cap features an inner sealing mechanism that prevents ink from drying out, keeping your pen ready whenever inspiration strikes. Like all TWSBI Eco, the Cosmo with Onyx model is fully disassemblable for cleaning and maintenance. A wrench and silicone grease are included for long-term care, though these accessories are not required for immediate use. Handle the nib and feed with care, as the feed is delicate but finely tuned for optimal performance.

The TWSBI Eco in Cosmo with Onyx is more than just a pen, it’s a little piece of the universe in your hand, perfect for journaling, note-taking, or adding a touch of cosmic elegance to your everyday writing.

Available nib sizes include Extra Fine, Fine, Medium, Broad, and Stub 1.1 mm to suit your preferred writing style.

TWSBI Eco Fountain Pen in Cosmo with Onyx Specifications

• Pen Material: Transparent acrylic barrel
• Nib Material: Stainless Steel
• Available Nib Sizes: Extra Fine, Fine, Medium, Broad, and Stub 1.1
• Cap Material: Cosmo resin with inner cap for ink seal
• Trim: Onyx black PVD accents
• Filling Mechanism: Piston-filling system (Bottled Ink Only)
• Pen Length, Closed: 5.46 in. / 138.8 mm
• Pen Length, Open (Cap Off): 5.18 in. / 131.5 mm
• Pen Length, Open (Cap Posted): 6.59 in. / 167.5 mm
• Pen Max Diameter, Barrel: 0.50 in. / 12.8 mm
• Pen Diameter, Grip: 0.36 in. / 9 mm
• Total Weight: 0.74 oz. / 21 g
• Postable: Yes (cap posts securely on barrel)
• Accessories include: Wrench and silicone grease for long-term maintenance
• Made in Taiwan