HP (Hewlett Packard) LaserJet Pro M521dn MFP (A8P79A) is a monochrome (black and white), workgroup, multifunction printer. It functions as a printer, copier, scanner and fax machine. It has a print resolution of 1200 x 1200 dpi, a scan resolution of 1200 x 1200 dpi, a copy resolution of 600 x 600 dpi and a fax resolution of 300 x 300 dpi. It has a print and copy speed of 42 pages per minute. The HP LaserJet Pro M521dn MFP has a 600 sheets total input capacity and 350 sheets output trays capacity. The total maximum media capacity is 1,100 sheest. The HP LaserJet Pro M521dn MFP media types are envelopes, transparencies, labels, plain paper, heavy-weight paper, cards, bond paper and recycled paper. It's media size is C5, A5, Executive, B5, A6, A4, Letter A Size, Legal and JIS B5. It has a monthly duty cycle of 75,000 sheets. It also features automatic duplexing, 128 MB RAM, ethernet and USB connectivity. HP LaserJet Pro M521dn MFP uses 55A and 55X black cartridge. Cartridge model numbers are CE255A and CE255X.