The TWSBI Diamond 50mL ink bottle is a unique glass bottle with an anodized aluminum top that is the perfect accessory for any fountain pen addict!
The bottle allows for easy refilling of your fountain pen by offering an upper reservoir that fills with ink when you turn the bottle upside down (cap on of course!).
The reservoir provides a set amount of ink to fill your pen and avoids the hassle of dipping your pen to the bottom of the bottle, trying to get each drop out as the bottle runs low.
As an added benefit to those who own the Diamond 530, 540, 580 or Mini fountain pen you can use the colored band attachment to refill your TWSBI fountain pen without having to use the nib at all!
Simply unscrew the front section of your Diamond fountain pen and attach it to the filling apparatus. Turning the piston knob of the fountain pen will draw the ink up into your pen. No more inky fingers!!