Amazon.com : Black & Blue Ink Cartridges for Fountain Pens. Big Pack of 20 Short International Standard Size Cartridges. Perfect for Calligraphy Pen. Universal Fine Design with Incredible Long Lasting Color :
Amazon.com : Wordsworth & Black Fountain Pen Ink Refills - Set of 15 Black - 15 Blue Ink Cartridges - International Standard Size - Length APPR 2.04 Inch - Base Diameter APPR 0.24 Inch - Disposable and Generic : Office Products
Sheaffer's Classic Ink Cartridge | Unsharpen
Amazon.com : Vivid Black Ink Cartridges for Fountain Pens. Amazing Big Pack of 20 Short International Standard Size Cartridges. Perfect for Calligraphy Pen. Universal Fine Design with Incredible Long Lasting Color :