Compatible with: Lexmark MS811dn, MS811dtn, MS811n, MS812de, MS812dn, MS812dtn Compatible Replacements Included: 3 pack 52D1X00 black Lexmark 521X Toner Cartridges Extra High Yield Delivers 45,000 pages just like the original Lexmark 521X compatible toner cartridge Average cartridge Page Yield* in accordance with ISO IEC 24711. *at 5% coverage (ISO/IEC standard) This is the extra high yield version of Lexmark compatible toner cartridge 521X