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65 products
65 products
The TWSBI Classic Sapphire fountain pen pairs timeless design with modern fountain pen engineering. Featuring a deep sapphire-blue resin body accented by polished metal trim, the Classic offers a refined, understated look that feels equally at home on a desk, in a journal, or in a professional setting.
Built with TWSBI’s dependable piston-filling system, the Classic allows you to fill directly from bottled ink while providing generous ink capacity for extended writing. Its smooth, rounded shape and balanced weight create a comfortable writing experience that’s ideal for everyday use.
The pen is fitted with a polished stainless steel nib available in a variety of sizes, delivering smooth, consistent ink flow whether you’re taking notes, writing letters, or journaling.
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance—perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance, perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
Official Release Date: August 27th 2025
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance, perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance, perfect for fountain pen enthusiasts who love to tinker.
The ever popular 580AL now with Onyx finish.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance. Its perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance—perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.
The TWSBI Diamond 580 fountain pen blends modern engineering with classic demonstrator style, making it one of the most beloved pens in the TWSBI lineup. Crafted with a faceted, diamond-cut barrel, the 580 beautifully showcases your ink while providing a comfortable, balanced writing experience for everyday use.
Built with TWSBI’s signature piston-filling mechanism, the Diamond 580 offers a generous ink capacity and smooth, consistent flow. The transparent body allows you to monitor ink levels at a glance, while the precision-engineered stainless steel nib delivers a reliable and customizable writing experience. Designed to be user-serviceable, the 580 can be easily disassembled for cleaning and maintenance—perfect for fountain pen enthusiasts who love to tinker.
Aluminum machined grip, connector, and piston rod.
AL Models have a smooth grip section.
ALR Models have a ribbed textured grip section.