TWSBI Diamond 50 Ink Bottle

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Silver (Black Cap)
Polished Silver (Polished Silver Cap)

TWSBI Diamond 50 Ink Bottle is designed with a reservoir to assist in filling fountain pens, and comes with a specific upper attachment designed to easily fill TWSBI Diamond 580, Classic, Mini, or Precision fountain pens.

The TWSBI Diamond 50mL ink bottle is a glass bottle with anodized aluminum top that is the perfect accessory for any fountain pen ink lover! Simply decant your ink into the bottle and follow one of the fill methods listed below.

To fill any fountain pen: Turn the bottle upside down (cap on of course!) and let the upper reservoir fill up. Then, dip your fountain pen or converter into the risen ink level and fill your pen as usual. The reservoir provides a set amount of ink to fill your pen to prevent the hassle of dipping your pen to the bottom of the bottle, trying to get each drop out as the bottle runs low. 

To fill a TWSBI Diamond 580, Classic, Mini, or Precision fountain pen: affix the colored band attachment to the glass bottle. Then, twist off the nib section of your TWSBI pen and attach it to the filling apparatus. While the pen body is attached, turn the piston knob of the fountain pen to draw the ink directly up into your pen. No more inky fingers!

  • Ink capacity: 50ml
  • Materials: Aluminum cap, Glass bottle
  • Includes reservoir for filling all fountain pens/ converters
  • Includes attachment for filling TWSBI Diamond 580, Classic, Mini, or Precision fountain pens
  • Top of Diamond 50 Ink Bottle interchangeable with top of TWSBI 70ml ink bottles
  • Please note: Bottle does not come with ink
  • Please note: This item is fragile! Protected shipping will be automatically applied

View all TWSBI products

About TWSBI:

TWSBI 三文堂 (San Wen Tong) is one of our earliest collection even before the store. TWSBI started as an OEM manufacturer for different western brands, and around 2009, they decided to start their own brand. With 50 years of experience in pen making, they took to fountain pen forums and gather users’ feedback. It was said that Pelican M800 was the model they were inspired. Most of their pens are transparent, so it’s really fun to see the ink color and it lasts for a very long time.

The name 三文堂 (San Wen Tong) comes from the Hall of the Three Rare Treasures, created by Emperor Qianlong as a memorial to three great masterpieces of Chinese calligraphy. The initials of the name “San Wen Tong” was reversed and thus turned into "TWS". The last letters "Bi" was added with its literal meaning of "writing instruments" in Chinese. Thus combining the two segments, creating TWSBI.