MICR toner cartridge is designed for use with Hewlett-Packard LaserJet 4000, 4000T, 4000N, 4000TN, 4000se, 4050, 4050T, 4050N and 4050TN. Cartridge contains magnetic image character-recognition ink for security purposes in printing checks. Cartridge is estimated to yield 10,000 pages at 5 percent coverage.