The OKI 9004391 Compatible High Capacity Black Toner Cartridge is a quality compatible toner cartridge offering great savings on buying the original OKI 9004391 without losing quality. The OKI 9004391 compatible saves money whilst also helping the environment in the process, printing clean and crisp images and text. The OKI 9004391 Compatible High Capacity Black Toner Cartridge prints approx 4000 pages at 5% average coverage. B2500, B2520, B2540, Office 2530,Fax 2510