Mini converter for the original Napoleon fountain pens taking standard international ink cartridges. Approximately 2-1/4" (56mm) long with the piston pulled completely out, 1-9/16" (39 mm) long with the piston pushed in, and 6 mm in diameter. Will not fit Rosetta Napoleon II, Kaweco Sport pens or Ohto Tasche pens. The Rosetta Mini Converter is slightly longer than an international cartridge (ink cartridge not included)