Genuine Lexmark supplies are engineered to work best together with your compatible Lexmark printer, delivering excellent print quality from the first page to the last. Essential to Lexmark print system performance, the Unison toner's unique formulation consistently delivers outstanding image quality, ensures long-life print system reliability, and promotes superior sustainability, all in an innovative shake-free print system. The Lexmark Return Program cartridge is a print cartridge sold at a discount in exchange for the customer's agreement that the cartridge will be used only once and returned only to Lexmark for remanufacturing or recycling. This single-use only cartridge will stop working after reaching the end of the rated life established by Lexmark (a variable amount of toner may remain when replacement is required). This cartridge may also automatically update the printer memory to protect the printer from counterfeit and unauthorized products. Recycle all your used Lexmark supplies by letting Lexmark take care of the details. It's simple, smart, and always free.