Fountain Pen Ink Refill Cartridges 24 Ink Cartridges (6 colors Variety Set) Black Blue Red Green Purple Pink - For Executive Writing Signature Calligraphy Pens Set Standard International Size NATURAL PH, NON-TOXIC. ZenZoi fountain pen ink refill cartridges have a neutral PH, professional coverage and quality providing a smooth flow with each stroke. UNIVERSAL, PRACTICAL SIZE. International/standard size of these cartridges make them generic and practical: they fit every fountain pen on the market that works with standard international cartridges (including all ZenZoi fountain pens). YOU WON'T RUN OUT. Big Value Pack of 24 cartridges assures you'll not run out fast. Eliminates the need to keep reordering often yet provides variety of colors suitable for all moods, usages and occasions. FULL COLOR VARIETY. Each pack includes theses colors: 4 Black, 4 Blue, 4 Red, 4 Green, 4 Pink and 4 Purple. If you want to purchase just Blue & Black 2-color Classic Set, please go to another listing by ZenZoi: https://www.amazon.com/dp/B01KA1MM4U 100% THRILLED CUSTOMER PROMISE. No-questions-asked, no hassle. If for any reason our product is not what you wanted just messaged us for a full refund or replacement - whichever you choose. With us you always shop with ease and comfort. So either you'll love your new set or it's complimentary.