TWSBI Diamond 580 Fountain Pen - ClearMakes the act of writing visible The TWSBI Diamond 580 Clear is a traditional piston filler stripped back to show you everything inside the pen. Seeing the workings and ink movement turns your writing into something you actually engage with. Built on TWSBI's reliable piston mechanism, smooth 580 nib, and a body that's lighter than the rest of the Diamond 580 range, it's one of our most popular pens for long copy writing. What sets it apart Full