Troy 02-81676-001 High Yield MICR Toner Secure Cartridge for HP LaserJet M501, M506, M527 Printers Part Number: 02-81676-001 Coordinating Non-MICR HP Part Number: HP-CF287X Cartridge yields approx. 18,000 pages with 5% coverage TROY Security Toner was created as a way to help prevent fraudulent alteration of documents The patented security agent forces a bright red stain to permeate through the document if chemical alteration is attempted