This is a 3-pack of premium compatible Q6511A (11A) toner cartridges, designed for HP LaserJet 2420, 2420d, 2420dn, 2430, 2430dtn, 2430n and 2430tn printers. Each black cartridge is custom built to replace HP Q6511A toner cartridges for crisp detail, sharp text and clear graphics. MTI © printing products give you consistent, professional results at 40-60% of OEM prices. MTI © toner cartridges are engineered to exceed industry standards of high yield and exceptional quality, and guaranteed to perform with HP LaserJet Printers. Every cartridge is factory tested and ISO approved. We offer an exclusive 30-day customer satisfaction guarantee and 1-Year Manufacturer Warranty. Our dedicated customer care staff is available 9 a.m. to 7 p.m, Monday through Saturday, to answer any questions and provide technical support.