MICR toner cartridges are specialty toners used by the banking industry for check processing. MICR is an acronym that stands for magnetic ink character recognition. Each MICR cartridge is filled with a special toner powder designed specifically for check printing. MICR toners print the bank routing number, account number and check number on a check (also known as the “MICR line”) offering security to both the consumer and their banking institution. The MICR toner formula works jointly with a specialized MICR font known as E-13B to produce a unique combination of characters on your check, reducing the risk of fraud during the check-processing period.