Genuine Brother LC-900HYBK high yield black ink cartridge, the yield is 900 pages at 5%. (Not Compatible with the DCP-310CN, MFC-410CN & MFC-620CN) For use in the MFC-3240C, MFC-3340CN, MFC-5440CN, MFC-5840CN, FAX-1840C, FAX-1940CN and FAX-2440C