Brother BU-100CL Belt Unit / Transfer Belt, Yield Up to 50,000 pages, Compatible Brother DCP-9040CN, HL-4040cn, HL-4050CDN, MFC-9440CN, MFC-9450CDN, MFC-9840CDW. This BU-100CL Belt Unit is designed as part of an entire printing system and tested to ensure optimum performance and component protection.