Fuser film sleeves compatible with MF645CX, MF641, MF643, MF643CDW, LBP621, LBP623CDW, LBP621CW, 1025, M175, M176, M177, CP1025NW, M251, and 276 models.Designed to support proper fusing function in laser printers and multifunction devices.smooth paper passage through the fuser unit and consistent print output.Replaces worn or damaged sleeves to maintain device performance.Installation is straightforward and aligns with standard maintenance procedures for compatible models.