This is one full color set of premium compatible Laser Toner Cartridges (Black, Yellow, Cyan, Magenta) for use in Xerox Phaser 6300 Printers. MTI © toner cartridges are engineered to exceed industry standards of high yield and exceptional quality, and guaranteed to perform with Xerox Printers. Every cartridge is engineered in an ISO-certified facility and factory tested before shipping. We offer an exclusive 30-day customer satisfaction guarantee and 2-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.