The FD-5000 Fuser Unit is a genuine Brother replacement part that helps deliver professional quality printouts for up to 100,000 pages (1). Designed for high-volume printing, it efficiently bonds toner to paper, ensuring uniform results and allowing your printer to continue producing high-quality prints over an extended period of use. (1) 1 Approximately 100,000 pages based on 5 pages per job (letter/A4 single-sided pages). The number of pages may be affected due to a variety of factors including but not limited to media type and media size.