Some of the most enjoyable aspects of writing with fountain pens stem from their longevity and the versatility of their ink -both in body and color- made possible by the variety of refill options available to fountain pen users. Cartridges are pre-filled and disposable tubes of ink that are valued for being easy to use and unlikely to make any mess, as well as often being offered in several colors. Bottled ink is stored inside pens via their ink converters, which use a variety of mechanisms to draw ink from bottles. Bottled ink offers a much more expansive range of hues, undertones, consistencies, and special qualities like shimmering or dual-tones. Many fountain pen owners enjoy collecting bottled inks and filling their pens themselves. Most fountain pens accept both ink cartridges and ink converters, but if you aren't sure which is the right fit for your pen, check out our Library, which has comprehensive information on the cartridge and converter compatibility of a large variety of brands. We offer a wide selection of cartridges and bottled inks to make your writing experience as well-fitted and personalized as possible.