The HP LaserJet 4100 is internet-ready workgroup printer with more speed, capacity, and intelligent printer management. Full-engine-speed 1200 dpi print quality in all document types for increased user productivity. Choose from a range of expansion options, including up to three expansion memory slots, two EIO interface slots, auto-duplex unit (standard on 4100dtn), and additional sheet feeders. Increased media flexibility via size sensors for letter, legal, A4, A5, B5, and custom sizes, plus additional 500-sheet paper feeder and envelope feeder.