The TWSBI ECO Piston Filler Fountain Pen – Carrara Onyx is a sophisticated "Marbled Edition" that brings the timeless elegance of Italian stone to your desk. This model features a unique white and grey swirled resin on the cap and piston knob, mimicking the natural veins of classic Carrara marble.
Because of the unique injection molding process used for the marbled resin, no two pens are exactly alike—your pen will have its own distinct pattern. This statuesque aesthetic is grounded by the stealthy Onyx Black plated trim and a matching black nib, creating a striking monochrome contrast.
The ECO (short for "Economical") is famous for bringing high-end piston filling mechanisms to an accessible price point. The built-in piston allows you to fill the pen directly from a bottle, holding a massive 1.76ml of ink. The crystal-clear barrel allows you to monitor your ink level while showing off the unique colorway.
True to TWSBI’s philosophy of user empowerment, the pen arrives in a presentation box that includes a wrench and silicone grease, allowing you to fully disassemble and lubricate the mechanism yourself—ensuring your pen lasts a lifetime.
In Stock & Ready
Every tool is personally dispatched from our hubs within 48 hours (2 business days).
Standard Tracking (Registered Airmail)
Expedited Priority (FedEx/DHL)
Our Logistics Commitment
Orders are handled at our precision fulfillment centers in Hong Kong or Taiwan. For our US community, we absorb import tariffs on Standard Shipping to keep rates fair.
*Note: US Expedited couriers invoice recipients directly for individual customs clearance and administrative fees (typically ~USD 30).
Rates are listed in USD; our system automatically converts these to your local currency at checkout.
