HP 645A Original LaserJet Toner Cartridge – Black | C9730APage YieldOriginally published by HP, this cartridge delivers an estimated 13,000 pages at 5% page coverageCompatibilityThe HP645A (C9730A) black toner cartridge is compatible with the following HP Color LaserJet models:HP Color LaserJet 5500, including variants (DN, DTN, HDN, N)HP Color LaserJet 5550, including similar variants (DN, DTN, HDN, N