TWSBI Eco Fountain Pen - Plum with Onyx Trim and Nib
A colour way you can turn red or pink
The TWSBI Eco Plum is a piston-filling fountain pen finished in a sophisticated crimson, with subtle red undertones, and a formal black trim. Just like a real plum, the subjective colour can vary from almost magenta through to red, depending on the ink you fill it with. Built for daily writing, it combines high ink capacity with reliable performance.
What sets it apart
- High capacity piston filling system for long writing sessions
- Smooth, consistent steel nib, across a range of sizes
- Deep plum tone with subtle warmth and depth
- Completely transparent barrel to monitor ink level
- Change the overall look by the ink colour you fill it with
Feel in the hand
The Plum feels warm, steady, and slightly more expressive than standard demonstrators. The colour adds personality without becoming distracting, making it easy to use for both everyday writing and more formal work.
Who it’s for
- People who want a demonstrator with subtle personality
- Writers who enjoy deeper, warmer colour palettes
- Lovers of red and pink inks, for easy colour matches
- Collectors already enjoying the plated Eco series
- Professionals who need to write fast, but want more style
Not for
- Users who prefer neutral or monochrome tones
- Those who want cartridge or converter convenience
- Anyone who prefers opaque or metal bodied pens
- Writers chasing flex or flair in the nib
Practical tips
Change the perception of the pen colour by the ink you choose. Make it look pinker with Sailor #831, make it look redder with De Atramentis Elderberry.
FAQs
Is it a limited edition?
Yes, usually there is one production run and then no more stock is available.
Is the Plum fully transparent?
Yes, it is a demonstrator with a completely clear barrel, allowing ink visibility. Only the cap and turning knob are opaque.
Does it use cartridges or converters?
No, it uses a built-in piston filling system
Is it suitable for beginners?
Yes, it is one of the most beginner-friendly piston fillers available
Can it handle document and shimmer inks?
Yes, with regular cleaning recommended
What nib does it use?
TWSBI stainless steel nib with a black onyx coating.Â
What’s included
TWSBI ECO Plum Fountain Pen
Wrench
Silicone grease
Instruction booklet
Free nib tuning by LarryPOST
Ink pairing suggestions
- Burgundy inks for a cohesive match
- Red inks for a energetic expression
- Deep blue inks for clean readability
Build your practice
- Collect the Eco plated range
- Replacement Onyx Eco nibs, for exploring line widthÂ
- Pilot Iroshizuku or De Atramentis Document ink to match Eco flow
Specifications
- Brand:Â TWSBI
- Brand series:Â Eco
- Launch:Â October 2025
- Origin:Â Taiwan
- Nib: Black Stainless steel
- Nib sizes:Â EF, F, M, B, 1.1mm stub
- Filling system:Â Piston filler (1.8mL)
- Body:Â Transparent polycarbonate
- Cap:Â Twist
- Diametre:Â approx. 13mm
- Length:Â approx. 139mm (capped)
- Weight: approx. 21g (capped)
- Comparable size:Â Lamy Safari, Pilot Metropolitan
The deep plum finish brings warmth and expression to your everyday.
