Toner cartridge delivers outstanding results page after page in your Lexmark X642E, X644E, X646E, X646EF and x646dte. Superior Lexmark design means precision pairing between printer and cartridge for value, quality and environmental responsibility you can count on. Lexmark Return Program cartridges are sold at a discount VS. The prices of regular cartridges in exchange for the customer's agreement to use the cartridge only once and Return it only to Lexmark for remanufacturing or recycling.