Compatible with: Lexmark MS810de, MS810dn, MS810dtn, MS810n, MS811dn, MS811dtn, MS811n, MS812de, MS812dn & MS812dtn Compatible Replacements Included: 4 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 Please contact us first with any product issues. We want all of our customers to be happy because happiness matters.