From the ink masters at J. Herbin, say hello to the rainbow of fountain pen cartridges. These are standard international snap-in cartridges, with each cylindrical metal tin containing six cartridges. Fits most fountain pens and e-rollerballs, except Waterman, Sheaffer, Parker, Lamy, A.T. Cross, Pilot/Namiki, Sailor, Platinum, Aurora, Fultz and Nakaya.