Drum unit is delicately balanced to provide even flow and distribution for high-quality results. Yield is approximately 50,000 pages based on three pages per job and 30,000 pages based on one page per job (A4/letter simplex pages). Easy-to-install design minimizes maintenance time for hassle-free replacement. Drum unit is designed for use with Brother HLL6250DW, L6400DW, L6400DWT, MFCL6750DW and L6900DW printers (sold separately).