This Lexmark 55B1000 Black Toner Cartridge is designed to work with a range of Lexmark printers, including the MX321adw, MS421dn, MS321dn, MX521ade, MS521dn, MS621dn, MS421dw, MX521de, and MS622de. It is a genuine OEM product that comes in factory-sealed retail packaging, ensuring that you get a high-quality and reliable toner cartridge.Print documents with sharp, black text and graphics with this laser toner cartridge. It is designed for use with laser print technology and is compatible with Lexmark printers. With dimensions of 5.28in x 2in x 4.57in, this toner cartridge is easy to install and replace. Get high-quality printing results with this black toner cartridge from Lexmark.