Lexmark E321, E323 print cartridges are designed for easy customer installation and quality performance. The Lexmark E321, E323 supplies are not compatible with other Lexmark Printers including the E320/E322. To help customers quickly identify the difference, the Lexmark E321, E323 supplies have a two-tone design. Average Cartridge Yield 3,000 standard pages. Declared yield value in accordance with ISO/IEC 19752. Prebate?supplies are now called Lexmark Return Program cartridges. Details of the license program remain the same. Only the name has changed. For a period of time, when you order a Return Program cartridge, you may receive a Prebate?cartridge. We appreciate your patience during this transition. Lexmark Return Program Cartridges are sold at a discount versus 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. Regular cartridges without this license/agreement sold at regular prices are also available. Regular cartridges are also recyclable at no cost through Lexmark Cartridge Collection Program.