Thornton's Fountain Pen Ink Cartridges Thornton's ink cartridges have a neutral PH, excellent coverage, smooth flow, on top of the most vibrant colors their ink does not clog your pen and is a fast drying one. The standard cartridges fit almost every cartridge/converter fountain pen on the market. The 12-pack features a plastic reclosable case that will help preserve the life of the unused cartridges. Every occasion deserves special attention and care...And so do you! We ensure that you always have the right support, whatever you need to do. Our Amazing Ink glides and effortlessly over the surface of the page, resulting in glorious strokes. Express yourself with Thornton's ! These ink cartridges work with the following pens: Acme, Ancora, Bexley, Bosserrt & Erhard, Caran d'Ache, Cartier, Colibri, Conklin, Conway Stewart, DaniTrio, Daniel Hetcher, David Oscarson, Delta, Diplomat, Dunhill, Elysee, Faber Castell, Inoxcrom, Itoya, Jean Pierre Lepine, Jorg Hysek, Kaweco, Krone, Latex, Libelle, Lominchay, Marlen, Michel Perchin, Montegrappa, Monteverde, Nemosine, Nettuno, Northpointe, OMAS, Osmiroid, Pelikan, Recife, Reform, Retro 51, Rotring, Schmidt, Schneider, Sensa, Sheaffer, Signum, S.T. Dupont, Stipula, Stypen, Taccia, Tombow, Underwood, Visconti, Waterford, Waterman and Yard-O-Led. Thornton's Ink Cartridges. Neutral PH. Excellent coverage. Smooth flow. Easy to install and replace. No additional parts required. Simple and easy to use. cartridges are a fantastically convenient way to fill your pen. Short International Standard Size. Disposable and Generic Ink Refill Cartridges. Fine Design with Long Lasting Shade.