Lexmark 140127X Black Toner Print Cartridge, Linea Series, Fits HP Laserjet 4000 High-Yield Extra Long Life. 65% more pages than Lexmark Standard Cartridge For use with HP LaserJet Series 4000, 4000N, 4000T, 4000TN, 4050, 4050N, 4050T, 4050TN Also for use with Canon EP-51 P/N LBP-1760