Toner cartridge is designed for use in Lexmark C540, C540DW, C540N, C543, C543DN, C544, C544DN, C544DTN, C544DW, C544N, C5460DTN, X543DN, X544DN, X544DTN, X544DW, X544N, X546DTN, X548DE & X548DTE. 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 & return it only to Lexmark for remanufacturing or recycling.