Compatible with: Lexmark MS810de, MS810dn, MS810dtn, MS810n, MS811dn, MS811dtn, MS811n, MS812de, MS812dn, and MS812dtn, MS710dn, MS710n, MS711dn Compatible Replacements Included: 1 Piece 52D1H00 black Lexmark 521H Toner Cartridges High Yield Delivers 25,000 pages just like the original Lexmark 521H compatible toner cartridge Average cartridge Page Yield* in accordance with ISO IEC 24711. *at 5% coverage (ISO/IEC standard) This is the high yield version of Lexmark compatible toner cartridge 521H Please contact us first with any product issues. We want all of our customers to be happy because happiness matters.