This is a new premium compatible MICR Cartridge for check and barcode printing. It is custom built to replace HP C3903A and Troy 02-18583-001 toner cartridges. HP LaserJet and TROY MICR only accept MICR cartridges that have been modified to TROY specifications. MTI © premium toner cartridges are specially engineered to include the TROY modification. All our products are factory-tested and ISO approved. We offer an exclusive 30-day customer satisfaction guarantee and 1-year Manufacturer Warranty. Our dedicated customer care staff is available 9 a.m. to 7 p.m, Monday through Saturday, to answer any questions and provide technical support.